MDS = How to tell if your on 4 or 8 cyl.
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MDS = How to tell if your on 4 or 8 cyl.
Somebody asked once if it was possible to put an indicator light on your vehicle to tell if you are in 4 or 8 cyl. mode...
I said it couldnt be done.
But, it peaked my curiousity.
And one of my techs and I killed an hour and built this little unit.
On my 06 1500 the signal wire is the brown and light blue wire on the TOP connector of the PCM.
Be careful - there are 2 of them - the other is for one of the injectors.
DO NOT use a test light on these wires or ANY bulb - use only an LED.
LEDs have such a low current draw it will not disrupt the PCM.
Green light = 8 Cyl.
Red light = 4 Cyl.
My wiring diagram is crude - but it gets the point across.
[IMG]local://upfiles/36453/059C3790C56B4373AADE7CD89A4F2524.jpg[/IMG]
[IMG]local://upfiles/36453/976CA83686BD43338EC53480CF021EBA.jpg[/IMG]
I said it couldnt be done.
But, it peaked my curiousity.
And one of my techs and I killed an hour and built this little unit.
On my 06 1500 the signal wire is the brown and light blue wire on the TOP connector of the PCM.
Be careful - there are 2 of them - the other is for one of the injectors.
DO NOT use a test light on these wires or ANY bulb - use only an LED.
LEDs have such a low current draw it will not disrupt the PCM.
Green light = 8 Cyl.
Red light = 4 Cyl.
My wiring diagram is crude - but it gets the point across.
[IMG]local://upfiles/36453/059C3790C56B4373AADE7CD89A4F2524.jpg[/IMG]
[IMG]local://upfiles/36453/976CA83686BD43338EC53480CF021EBA.jpg[/IMG]