First I would like to thank everyone in advance for providing assistance. Yesterday I started having issues with my '04 Crossfire not starting. The symptoms are identical to the Mystery No Start issue but that does not appear to be the problem. Below are the symptoms.

Symptoms:

• On two previous occurrences the car stalled on me within seconds of starting but it would always fire back up without any hesitation. I did not think this was an issue as this only happened twice in the last 6 months.
• Yesterday the car failed to start all together. The starter motor does not turn and there is no noise coming from the engine.
• The interior reading lights and the radio will not turn on but all other accessories (headlight, turn signals, instrument cluster…) power right up.
• The radiator cooling fan engages as soon as the key is turned to the ON position.

Diagnostics:

• Checked battery – All was good as it was replaced two months ago.
• Checked all fuses and all appear to be good.
• Performed the Mystery No Start fix by re-soldering connection on the Relay Control Module (RCM) but this did not resolve the issue. As I was not confident that I did the re-soldering correctly I purchased a new RCM from Mercedes and replaced the unit. The car still does not want to start.
• No CEL while car was running.

I am not sure what is the issue and am not sure what else I should check. Does anyone have any idea what could be the problem?

Thank you,
-Amer

 

I would not jump to the conclusion that all the symptoms are related.

The simple explanation would be that the starter has failed and that is why the engine does not turn over. Is power getting to the starter, maybe the grounding of the starter or battery is poor. There was a thread a while back that had the cables from the battery being corroded inside the sheathing and that caused problems.

If you have a manual transmission I would look at the clutch interlock and see if that is working correctly. Autos have a similar switch that could have failed.

Clean the terminals and grounds and check that there is power to the starter, if there is power it should turn the engine over. Power has to go to the starter solenoid maybe there is none reaching it.

Some of these symptoms may have nothing to do with the car not turning over, the fan may have been starting as soon as you turn the key for some time.

I was talking to an older mechanic fifteen years ago, the problems on my car had baffled all the experts in the shop and the Chrysler technical reps as well. They told him to look at it, so he started from the basics. He found the error in an hour without the aid of computers and manuals.

 

Giving a quick look over some circuit diagrams, I would start at the "underhood fuseblock" for power to the appropriate fuses with the key on. Also check for problems at the power splice block located in the same area. Process of elimination.

James

 

Bump ---- ideas needed.

 

Thanks Onehundred and James!!!

I will start looking at the circuit diagrams in the repair manual as well as check the power to the starter. I still think that the radio and interior lights not working is related as well as the cooling fan kicking on.

I did forget to mention that two days ago when the problem started the car did start without any hesitation but immediately stalled and would not start back up. The radio was working when the car started but refused to come on after the starting issue. Not sure about the interior light as I did not pay much attention to this. I do not recall the cooling fan ever comming on before with the ignition set to ON. I could be wrong but I do keep my car in a small garage and the cooling fan at full speed sounds like a jet engine taking off.

Any other ideas?

Thank you,
-Amer

 

Last but not least....the ignition itself...many have had problems with a sticky key...and have had to repair or replace the ignition. If you have a test light, like for power up to the ignition...

 

I finally figured out the problem. It ended up being a loose ground connection located behind the yellow splice block in the fuse box.

Thanks everyone for your suggestions and help!!!

-Amer

 

I had a similar issue. Drove around town a bit then stopped at the grocery store. When I came out the car would not start, no lights came on on the dash. The gear shift would not move so I couldn’t push the car out of the parking spot to get in position to jump the (new) battery. Remote key would not lock doors. After several tries nearly 4 hours later the seat belt light came on when not trying to start the car, but nothing else. Awhile later the remote key suddenly did work, tail lights flashed and finally the car started. Drove around the block and turned off the key but the radio stayed on. Car started up easily immediately and I was able to turn off the radio. Car repair guy said unless he can duplicate the problem he has no way of telling what is wrong so he can’t fix anything, it has been at his shop for 3 days and starts fine every time. Several times in the past the radio has stayed on after turning off the engine. Seems like an electrical issue to me. Repair guy said maybe the positive battery cable is corroded on the inside but he can’t tell until he cuts it open. New cable is over $300, he can’t find an after market one. I’m afraid I’ll get stranded somewhere

 

Sounds like a flaky battery to me. I had bought a new battery back in 2017, three months later, had same thing TOTALLY DEAD. I popped the hood, then walked to my truck to get wrenches, realized I needed my keys from the car to unlock the truck.

Went back to car, before pulling keys I tried it again, car turned over slowly like the battery was weak, but started.

Anyway, took battery back for warranty replacement. It's never done it since.

 

Would the battery die then come back to life without being jumped/charged?

 

Yes . . . it can happen when one of the positive or negative plate's interconection crack somewhere. Voltage drop can occur sudently and come back later when the contact come back at the craked point . How Does A Car Battery Work? (napaonline.com)

Daniel

 

New cable $300? What is it made from ? Gold!

 

A battery cable is a battery cable, it just needs to be the correct length?

 

I’ll share your info with my mechanic, he thought it might have to do with excessive corrosion inside the positive cable.
so where would he look for a crack?
I thought maybe its a problem with a fuse, but I expect he would have checked the fuses already.

 

My mechanic said the positive cable is long and winds around and is difficult to access, it would cost over $500 to replace… and he won’t even know if that’s the problem until he opens up the cable, then it has to be replaced.

 

It isnt' a fuse.
The crack is in his logic. "Mechanics" can replace a crankshaft and rebuild an engine and lot of stuff I can't do. BUT DO NOT ask one of them to troubleshoot even basic electrical issues.

I still say battery - but then, I'm not standing next to your car, I"m only going on what little you have said.

 

Battery is all that explains ALL of this, this is NOT sounding like our "Mystery No Start", unless you are confused and some lights really DID come on. To be sure, NEXT TIME it does this, simply leave key in "ON" for 45 seconds, if the engien fan runs very fast, it's the RCM no-start, easy fix.

If not, then we go back to battery or battery cables - but every time ti's the battery cable, a visual inspection shows it - no need to x-ray the cable clamps.

If you had cheap, aftermarket battery cables, I'd suspect the internal crimp, etc. With factory cables, I've (we've?) seen no such failures.