2001 ML 430 aprox 100K miles. Not sure what happened but yesterday the car would not start. Turn the key and nothing happened. Headlights stay bright when the key is turned and no start. What I did notice out of the ordinary was the only dash board lights to come on were the SRS and Air bag lights. I can recreate the dash board lights today by switching the car on to accessory. The same two lights come on. Car started today without charging the battery so that rules out battery problems.
I think I have a bad ignition switch but I am not sure if a relay is between the battery and the ignition switch? Looking over a Mitchel wiring diagram I cannot find anything in between the battery and the ignition switch. Has anyone seen this problem before or knows if battery power is direct to the ignition switch?
Thanks John

Ignition switch powers up several relays that power up the car.

Circuit 15 relay & circuit 15R relay, possibly 1 of those relays are the problem.

They are in the main fuse box underhood.

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The car started for a couple of weeks, now the problem is back. I found the K-15 relay in the fuse box under the hood. I do not get power to terminal 85 at the relay. I also found another K-15 relay near the passenger foot area. I do get power to terminal 85 at that relay and it does work. Not sure what to check next. I did try a new ignition switch with no change in the problem. Thanks John

Found the problem. Loosened the fuse panel in the engine compartment & pulled it out of the fuse box. Disconnected & reconnected all electrical connections on the bottom of the fuse panel. About 20 to 25 different connections under there. Not 100% sure the problem went away for good but the car starts again. Hopefully there was a bad connection on one of the terminals. John

Problem is back. Does anyone know where I can get a hold of a wiring diagram as to how the ignition switch connects to the 15 & 15R relays? Thanks John

what was the final fix? I am having near identical problems.
thanks

Any updates on solutions for this issue?

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Jim