e320 no crank.
I've jumped the starter relay (k40 relay i believe) and the engine cranks good but doesn't fire, so it can't be the battery or the starter.
I tested that relay and switched it out still nothing. Tested every fuse I can find all good. Also both in park and neutral won't crank in ether.
I've been referring too a starter wiring diagram I found online. It shows a violet wire going from the ignition switch to the pcm for the start signal, tested power at that wire, no voltage in start position.
I tried jumping power to that violet wire to 'trick' the ecu into starting that didn't do anything.
So I'm thinking I'm down to it ether being the ignition switch, the key itself or a wiring issue. But I need a wiring diagram to go any further.
Thank you for reading through this any advice or tips would be appreciated.
Also with it warmed up if I tap 12v to the violet wire it with the key in run position it starts up. With that detail I'm inclined to believe when I tested that I had a bad connection.
Is there anything in the wiring for the pcm that could be effected by temperature or is it 100% the pcm.
I'm leaning towards the computer itsself being bad.
Does anyone have a pin out of the ecu for this model so I can make sure its getting proper power and ground when I'm having this issue?
Not sure how the trans could cause it unless the neutral safety switch was installed incorrectly. Good luck and let me know any progress.
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I took apart the relay and can't find any bad solder joints. But as I said before when the vehicles at room temp it starts. So I left the car in the shop and put the k40 relay outside. When I reinstall the k40 cold it won't crank. When gets up to room temp it starts... Did they figure out yours?
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