an operation of one type of a prior - art turn signal will first be described in order to emphasize benefits achieved by the invention . in brief , in fig3 b , a right - hand turn signal 6 a flashes an amber light on and off while the two white parking or drl lights 4 remain continuously illuminated . this event will be explained step - wise . in fig3 a , the vehicle 3 displays white parking or drl lights 4 , but no turn signal . in fig3 b , the right - hand turn signal 6 a is momentarily illuminated and emits the amber light . the dilution described earlier may occur at this time . then , in fig3 c , the right - hand turn signal 6 a temporarily goes dark between flashes . next , in fig3 d , the situation of fig3 b is repeated , wherein the right - hand turn signal 6 a is again illuminated . the sequence of fig3 a through 3d continues until the turn by the vehicle 3 is completed and the turn signal is cancelled . in contrast , the embodiments described herein provide control of the parking and drl lights and turn signal lights in various embodiments or environments , such as when the lights are housed in separate housings ( fig4 a - 4d ) or when they are housed in a common housing as illustrated in fig6 - 9b both illustrative embodiments will now be described . fig4 a - 4d illustrate operation of one embodiment of the invention and shows right parking or drl light sources 10 adapted to generate white light in a vehicle v which are clearly separate from right turn signal lamp or light source 12 which is adapted to generate amber light . it should be understood , however , that these colors could be different if desired . left parking or drl light sources 14 and left turn signal light sources 16 are also provided . in brief , in fig4 b , when the turn signal or light source 12 is illuminated , it generates an amber color and the adjacent parking or drl light source 10 does not generate the white light or different color . then , when the amber turn signal or light source 12 is extinguished , the adjacent white parking or drl light source 10 is re - illuminated . that is , the white parking or drl light source 10 and the amber turn signal lamp or light source 12 are not illuminated together , but they alternate in white and amber emitting light , respectively . thus , both the parking or drl light source 10 and turn signal lamp or light source 12 flash , but alternating . the same functionality applies to the left - hand parking or drl light source 14 and the left - hand turn signal lamp or light source 16 . however , this particular flashing of both the amber turn signal lamp or light source 12 and the adjacent parking or drl light source 10 only occurs when the parking or drl light source 10 is illuminated and a turn signal request occurs at the same time . at other times , when the parking or drl light source 10 is illuminated , but no turn signal request is issued , the white parking or drl light source 10 remains continuously illuminated in the usual manner . alternatively , if the parking or drl light source 10 is off and a turn signal request is issued , the turn signal light source 12 flashes in the conventional manner . again , the left - hand parking or drl light source 14 and turn signal light source 16 operate similarly . to repeat , in one form of one embodiment of the invention , the amber light generated by the turn signal light source 12 in fig3 b and its adjacent white parking or drl light source 10 are caused to flash alternately . that is , when the turn signal light source 12 is on , the adjacent parking or drl light source 10 is off . conversely , when the turn signal light source 12 is off , the adjacent parking or drl light source 10 is on . the sequence will be explained step - wise . in fig4 a , the parking or drl light source 10 generates white light and the parking or drl light source 10 is continuously illuminated during normal operation of the vehicle v . in fig4 b , the right - hand turn signal light source 12 is momentarily illuminated when there is a call for a right - hand turn signal . at this time , one embodiment of the invention extinguishes or terminates the adjacent parking light , which is also located on the right - hand side of the vehicle v . then , in fig4 c , the amber light from the right - hand turn signal light source 12 is extinguished , as occurs during normal flashing of a turn signal , the right - hand parking or drl light source 10 generates white light and becomes illuminated . then , as in fig4 d , when the right - hand turn signal light source 12 becomes illuminated again , as occurs during normal flashing , the amber light is generated , but the adjacent parking or drl light source 10 is extinguished . the sequence of fig4 a through 4d continues until the turn by the vehicle v is completed , and the turn signal is cancelled . the same sequence applies to the left - hand parking light or drl light source 14 which generates white light and adjacent left - hand turn signal light source 16 which generates amber light . it should be understood that during the sequence of fig4 a - 4d , the opposite side parking or drl light source remains illuminated at all times . in the example , the left - hand parking or drl light source 14 remains illuminated continuously , and its adjacent turn signal light source 16 ( fig4 a - 4d ) remains dark at all times during activation of the right hand turn signal . this alternate illumination of ( 1 ) the right - hand turn signal 12 and ( 2 ) its adjacent parking or drl light 10 reduces or eliminates the dilution described above . further , this operation gives the appearance that the parking light signal 10 remains continuously illuminated during the operation of the turn signal 12 . fig5 a - 5d illustrate the sequence of fig4 in simpler terms using just the parking or drl light sources 10 and turn signal light sources 12 . in fig5 a , the turn signal light source 12 is off , and its adjacent parking or drl light source 10 is on . in fig5 b , the turn signal light source 12 is on in response to a driver actuating a turn signal level or switch ( not shown ) inside the vehicle v . note that when the turn signal light source 12 is on , its adjacent parking or drl light source 10 is off . in fig5 c , the turn signal light source 12 is off , and the adjacent parking or drl light source 10 is on . in fig5 d , the turn signal light source 12 is on , and the adjacent parking or drl light source 10 is off . this sequence continues until the turn signal is cancelled . the previous embodiment was described using a conventional parking or drl light and turn signal housings ( i . e ., one for each function ). fig6 and 7 a - 8 illustrate another form of an embodiment of the invention , wherein the parking light and turn signal light are not visibly separated and are housed in a common housing . a single lighting and / or signaling device 20 contains light sources 10 and 12 in the form of light - emitting diodes or leds 22 and 24 , respectively , within a single housing 20 a , which is covered by a conventional single lens 26 . the parking or drl led 22 is white in color and acts as the parking light . led 24 is amber in color to provide a turn signal , both as described above . in one embodiment , the light sources are two chips from a single led ( called bichip led ). according to another embodiment , each light source are a chip of a single led ( called monochip ), leds being distinct from one other . alternately , two different separate or integral lenses ( fig6 ) can be used , separated at a divider 26 a . further , one lens or a portion 26 b of the lens 26 that covers or is in front of the turn indicator led 24 may be colored amber to act as a filter to generate amber light , even if a white diode were used as the turn indicator led 24 . it is important to note that with the arrangement of fig6 , only a single housing 20 a is required for this embodiment . note also that the leds 22 and 24 are hidden behind the lens 26 and permit or facilitate a more global integration of lamp designs and , advantageously , a reduction in space required for the separate functions . for ease of illustration , a single led 22 and led 24 for each function is presented , but it should be understood that a plurality of leds may be used for each function . fig7 a - 7d illustrate in simplified form the single housing 20 a and leds 22 and 24 . during operation , the operation sequence shown in fig7 b - 7e occur . in fig7 b , the parking or drl light source or led 22 is illuminated , and generates light that is white . the turn signal light source or led 24 is off at this time . in fig7 c , the parking or drl light source or led 22 is off , and the turn signal light source or led 24 is illuminated and generates light that is amber in color . in fig7 d , the parking or drl light source or led 22 is illuminated and generates light that is white . the turn signal light source or led 24 is off at this time . in fig7 e , the parking or drl light source or led 22 is off . the turn signal light source or led 24 is illuminated and generates light that is amber in color . fig8 illustrates a significant feature of one embodiment of the invention . the turn signal , which is visually transmitted to other drivers , comprises two colors which alternate in time . the colors are white and amber in this case , and they can be viewed as time - multiplexed . this approach is different from an ordinary turn signal , which comprises a single flashing color . in fig8 , the single - housing 20 a approach of fig6 and 7 a - 7 b is utilized . in fig8 , image a illustrates two white parking lights being projected or generated by the parking or drl light source or led 22 on each side of the vehicle v . in image b , a left - hand turn signal has been actuated by the driver , so the left - hand white parking light source or led 22 is turned off and has been replaced by a display of the amber turn signal light generated by the turn signal light source or led 24 . note that the amber light emanates from the same single housing 20 a and lens 26 as the previous white parking light did . in image c of fig8 , the amber light of image b is turned off and is replaced by the white parking or drl light generated by parking or drl light source or led 22 which is energized . then , in image d , the left - hand parking light generated by the parking or drl light source or led 22 is turned off and is replaced by the amber light generated by parking or drl light source or led 24 which is energized . therefore , in the sequence of fig8 , a turn signal on the left side of the vehicle v ( as viewed by the driver ), takes the form of a light which flashes white , then amber , then white , then amber , and so on . in contrast , an ordinary turn signal flashes , for example , amber , then nothing , then amber , then nothing , and so on . of course , the right - hand turn signal or light source or led 24 and parking or drl light source led 22 operate in the same manner in the illustrative embodiment . a control system 30 implements the operation for the embodiments described above . fig6 and 9 a - 13 illustrate details of such a control system . prior to explaining those fig6 and 9 a - 13 , a simplified equivalent circuit or control shown in fig9 a , will first be explained for ease of understanding . in fig9 a , a voltage source v 2 represents the main battery of the vehicle v of fig8 . in fig9 a , switch s 1 represents a parking light switch so that the parking or drl light source 10 is always energized during predetermined conditions under control of the driver , and switch s 2 represents a turn signal switch ( not shown ), which is commonly under the control of the operator of the vehicle and is typically on the left side of the steering wheel , at least in cars commonly used in the united states . when the switch s 1 is closed ( for example , when the vehicle v is started or the driver actuates the parking lights ) and switch s 2 is open , the control circuit 30 in fig8 causes switch q 1 in fig9 a to close , in a manner described later herein , thereby energizing parking or drl light source or led 22 to generate the white parking or drl . the turn signal light source or led 24 is not energized and remains dark . when the switch s 2 alone is closed , as when the driver actuates a turn signal , and switch s 1 remains open , the control circuit 30 in fig8 causes switch q 4 in fig9 a to close and open at a rate of about 1 . 51 hertz ( hz ). this causes the turn signal light source or led 24 to flash at that same rate of about 1 . 51 hz . the parking or drl light source or led 22 is not energized and remains dark during flashes of the turn signal light source or led 24 . the switch q 2 remains off because the switch s 1 is open if both switches 51 and s 2 are closed , as when the parking lights are on and the driver actuates a turn signal , the control circuit 30 causes switch q 1 to periodically open and close , and switch q 4 to assume the opposite state . that is , if q 1 is closed , then q 4 is open . if q 1 is open , then q 4 is closed and so on . this causes one , but not both , of either parking or drl light source or led 22 or the turn signal light source or led 24 to illuminate . this alternate illumination is indicated and summarized by a plot or timing diagram td in fig1 b . switch q 2 in fig9 a assists this function to diphase the ti signal from drl / pl therefore you have opposite state on drl / pl signal detailed on fig1 b . fig9 b shows the switches s 1 and s 2 of fig9 a . block sw in fig9 b contains definitions , which will be utilized to facilitate understanding . as block sw shows , when switch s 1 is open , it is defined as being in state a . when closed , switch s 1 is defined to be in state b . when switch s 2 is open , it is defined as being in state c , and when closed , switch s 2 is defined as being in state d . for ease of understanding , reference is made to the parking or drl light source or led 22 only , but this description applies to the parking or drl light sources 10 and 14 mentioned earlier . hence , the description herein relative to the turn signal light source or led 24 equally applies to the turn signal light sources 12 and 16 . in fig9 b , voltage sources v 2 and v 3 represent the main battery of the vehicle v . as in fig9 a , switch s 1 controls the parking or drl light source or led 22 . if that switch si is open in fig9 b , then the drain d 1 of field effect transistor ( fet ) q 1 is floating , so no current can pass to the parking or drl led 22 , which remains off , as indicated . transistor q 2 , which is an npn bipolar junction transistor , bjt , does nothing at this time . it behaves as an open circuit because its base b 2 is pulled to ground by resistor r 2 , which shuts off q 2 . also , its collector c 2 is not applied to a source voltage at this time ( because switch s 1 is open ), which means that no current can pass through the transistor q 2 . as in fig9 a , switch s 2 controls the turn signal light source or led 24 . for simplicity , only a single switch s 2 is shown . however , in practice , there are two such conventional switches , both identical in function . one controls the left - side turn signal , and the other controls the right - side turn signal . fig1 , later explained , provides an example of left and right side operation . when switch s 2 in fig9 b is open , as shown , the gate g 4 of fet q 4 is pulled to ground by resistor r 5 , causing q 4 to act as an open circuit . no current flows through the turn signal light source or led 24 , so it is off . therefore , in fig9 b , switches s 1 and s 2 , which are both open , cause both the parking or drl light source or led 22 and the turn signal light source or led 24 to be off at this time . in fig1 , switch s 1 is closed . this pulls gate g 1 of transistor q 1 to a higher voltage , thereby turning on q 1 . in turn , this causes current 11 to flow through parking or drl light source or led 22 . however , bjt q 2 is off because its base b 2 is pulled low as explained earlier . this is true even though its collector c 2 now has a voltage applied by way of resistor r 1 . in addition , fet q 4 is off , for the reasons explained in connection with fig9 b . therefore , at this time , with switch s 1 closed and switch s 2 open , the parking or drl light source or led 22 is on and the turn signal light source or led 24 is off . in fig1 , an example of switch s 2 being closed ( i . e ., a call for turn signal ) and switch s 1 open ( indicating no parking or drl lamp ) will now be explained . as shown , switch s 1 is open and switch s 2 is closed in the example . fet q 1 is off because its drain d 1 is floating as is its gate g 1 . the parking or drl light source or led 22 receives no current and is , therefore , off . the closed switch s 2 pulls the base b 2 of bjt q 2 to a high voltage . however , since switch s 1 is open , there is no voltage applied to collector c 2 of bjt q 2 , so bjt q 2 is off . the closed switch s 2 applies the train of voltage pulses indicated by v 1 to the gate g 4 of fet q 4 . when a high pulse , vhi , is applied , transistor q 4 turns on , and the turn signal light source or led 24 is pulsed to go on . when a low pulse , vlo , is applied , transistor q 4 turns off , terminating the current through turn signal light source or led 24 . therefore , in fig1 , the parking or drl led 22 is off , and the turn signal light source or led 24 pulses or flashes on and off . in fig1 , both switches s 1 and s 2 are closed . this will occur when the parking or drl light source or led 22 is illuminated , and the driver activates a turn signal by turning the turn signal lever ( not shown ) on the steering column ( not shown ). the circuit of fig1 will reside in one of two conditions at this time , depending on whether vhi or vlo of voltage train v 1 passes through switch s 2 . assume that vhi is passed through switch s 2 in fig1 . vhi pulls the base b 2 of bjt q 2 to a high voltage , thereby turning on bjt q 2 . in turn , that pulls the collector c 2 to a low voltage , thereby pulling the gate g 1 of fet q 1 to a low voltage . this turns off fet q 1 , so parking or drl light source or led 22 is turned off at this time . note that voltage vhi is also applied to the gate g 4 of fet q 4 , thereby turning on fet q 4 , which turns on the turn signal light source or led 24 . therefore , in fig1 , when vhi of voltage train v 1 is passed by switch s 2 , the parking or drl light source or led 22 is off and the turn signal light source or led 24 is on . in fig1 , it is assumed that vlo of voltage train v 1 is passed by switch s 2 . that applies a low voltage to the base b 2 of bjt q 2 , thereby turning off bjt q 2 , which turns off the turn indicator led 24 . in this regard , voltage vlo is also applied to the gate g 4 of fet q 4 and pulls the gate g 4 to a low voltage . this turns off fet q 4 , thereby turning off turn indicator led 24 . now the gate g 1 of fet q 1 is pulled to a high voltage , by way of resistor r 1 being connected to voltage v 2 . this turns on fet q 1 , thereby illuminating parking or drl light source or led 22 . therefore , in fig1 , the parking or drl led 22 is pulsed on when the turn signal light source or led 24 is pulsed off . to repeat , when switches s 1 and s 2 are both closed , the situation alternates between that of fig1 and that of fig1 . when parking or drl light source or led 22 goes or is pulsed on , the turn signal light source or led 24 is off . when the latter turn signal light source or led 24 goes or is pulsed on , parking or drl light source or led 22 is off . from one point of view , in fig1 and 13 , switches s 1 and s 2 both attempt to turn on their respective leds . switch s 1 attempts to turn on the parking or drl light source or led 22 . switch s 2 attempts to turn on the turn signal light source or led 24 , but only when vhi is applied to switch s 2 . however , vhi turns off the transistor q 2 , thereby turning off fet q 1 . consequently , the event which turns on fet q 4 , namely , the occurrence of vhi , serves to also turn off fet q 1 , by turning on bjt q 2 . so the parking or drl light source or led 22 and turn signal light source or led 24 are forced into opposite states . when one is on , the other is off . 1 . a significant feature of one embodiment of the invention is that both lamps or leds 22 and 24 in fig6 can be contained within the single housing 20 a as shown in fig6 - 7e , compared with the dual - housing approach of the embodiment of fig4 a - 5d . this can reduce manufacturing and assembly costs . further , the leds 22 and 24 can be more closely spaced together in the single housing 20 a shown in fig6 compared to the two housing approach shown in fig4 a - 5d , thereby reducing size and space requirements . this provides the result that , when the leds 22 and 24 alternate in illumination , they resemble a single flashing item through lens 26 , which alternately produces white and amber light . this situation is contrasted with the embodiment of fig4 a - 5d wherein any analogous flashing would be perceived as a flashing light which jumps left and right between 10 and 12 ( for a right - hand turn or 14 and 16 for a left - hand turn ), similar to a so - called “ wig - wag ” crossing lights used at railroad crossings . 2 . one characteristic of the single housing 20 a in fig6 is that two separate , independently operable , illumination assemblies ( one pair on each side of the vehicle v ) are not present or required , as in the prior art shown in fig2 . 3 . it should be understood that the control system or circuit 30 of fig9 a and 9b will control , for example , the turn signal on the left side of the vehicle v and the parking light or drl also on the left side of the vehicle v . that is , led 22 is located on the left side , as is led 24 . the identical control system or circuit 30 controls the turn signal and parking light or drl on the right side of the vehicle v . these two control systems are represented separated by blocks 30 a and 30 b in fig6 . it should be understood that the control system or circuit 30 may be a separate component integrated on the same printed circuit board as the control circuit components ( not shown ) in each light housing , such as light housing 20 a . alternatively , the control system or circuit 30 could be provided on a separate printed circuit board mounted with other vehicle electronics ( not shown ), such as with conventional turn signal electronics . 4 . although preferred , the single - lens , single housing 20 a approach of fig6 is not required . the dual - housing system of fig4 a - 5d can be used with the embodiments of the invention . 5 . fig1 illustrates the components labeled as left side are analogous to those described in fig9 a - 13 and operate similarly . those components control light sources or leds 22 l and 24 l , which are on the left side of the vehicle v . the components labeled right side control light sources or leds 22 r and 24 r , which are on the right side of the vehicle v . there are at least two differences between the left side and right side components . one is that switch s 1 is eliminated from the right side . switch s 1 l controls both light sources or leds 22 l and 22 r . a second difference is that no additional voltage train v 1 ( as shown in fig9 b - 13 ) is shown on the right side . a single voltage train v 1 l is provided . it is used by the left side or the right side components when needed , but not both at once . in fig1 , switch s 1 l turns both park lamp leds on and off in the manner described earlier relative to fig9 b - 13 . if switch s 1 l is off or open , then ( 1 ) switch s 2 l operates the left turn signal light source or led 24 l , and ( 2 ) switch s 2 r operates the right turn signal light source or led 24 r , in the manner described earlier relative to fig9 b - 13 . if switch s 1 l is on or closed , then if switch s 2 l is closed , the left parking or drl light source or led 22 l flashes alternately with the left turn signal light source or led 24 l in the manner described earlier . the right parking or drl light source or led 22 r is illuminated continuously and right turn signal light source or led 24 r is off . if switch s 1 l is closed and if switch s 2 r is closed , the right parking or drl light source or led 22 r flashes alternately with the right turn signal light source or led 24 r . note that the left parking or drl light source led 22 l is illuminated continuously and left turn signal light source or led 24 l is off . during normal operation , an interlock il in fig1 is generally provided to prevent turn indicator switches s 2 l and s 2 r from being actuated simultaneously because simultaneous actuation would imply issuance of a simultaneous turn in both the left and right directions . in contrast , if a hazard warning signal were initiated , the hazard warning signal would flash both sides at the same time . the apparatus of fig1 prevents a parking lamp led from illuminating at the same time as its adjacent turn signal led . for example , if left turn signal light source or led 24 l is energized or illuminated , then the circuit 30 prevents left parking or drl light source or led 22 l from illuminating simultaneously . those two light sources or leds 22 l and 24 l are required to illuminate or flash alternately at different times as explained earlier . 6 . for ease of understanding , fig1 includes a simplified representation of fig1 . the bracket labeled prior art indicates that leds pl and sl are controlled independently by respective switches sa and sb . ( in practice a relay or equivalent , not shown , may be interposed between a switch and the led , to handle a large current .) that is , the operation of switch sb does not affect the illumination of led pl . they are independent . in contrast , the embodiments being described provide the control system and circuit 30 within the bracket labeled 30 . the control system and circuit 30 makes the operation dependent as explained above . for example , the left park lamp led , labeled pl - l , cannot operate independently from the left turn signal led , labeled sl - l . further , because of the interlock il , the left turn signal led , labeled sl - l , cannot operate independently of the right turn signal led , which is labeled sl - r . 7 . fig1 a is a truth table that summarizes the different operational states and illustrates one type of dependency in the operation . when both switches s 1 and s 2 in fig9 a are open , both leds 52 and 53 are off , as fig1 , top row , indicates . as illustrated in the second row of fig1 , when switch s 1 is open and switch s 2 is closed , the appropriate turn signal flashes and no parking lights are displayed . as the third row of fig1 indicates , when switch s 1 is closed and switch s 2 is open , the parking or drl lights go on , but no turn signal illuminates . as the last row in fig1 indicates , when both switches s 1 and s 2 are closed , the appropriate turn signal light source or led 24 alternates with its adjacent parking light source or led 22 . it should be understood that the non - adjacent parking light source or led 22 illuminates continuously and the other turn signal light source or led 22 is off . 8 . fig1 illustrates the range of flash rates for a turn signal allowed in north america . this illustrates that a primary factor which would be allowed to change is the flash rate / frequency of the turn signal , which would affect the countering flash of the parking or drl light source throughout the duration of the turn signal . this invention , including all embodiments shown and described herein , could be used alone or together and / or in combination with one or more of the features covered by one or more of the claims set forth herein , including but not limited to one or more of the features or steps mentioned in the bullet list in the summary of the invention and the claims . while the system , apparatus , process and method herein described constitute preferred embodiments of this invention , it is to be understood that the invention is not limited to this precise system , apparatus , process and method , and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims .