SOLVED: W124 Randomly Died on Me (Loose battery terminal)

[mnessari]

Hello all! I managed to lock myself out of my account but I am back in now! A quick update on my resurrected W124 with the help of the members here I was able start the car, then got her running smoother, and just recently she passed smog!!!

I was driving yesterday to have my AC recharged and the car died on me while at a red light. The ABS and ASR light came on as well as the triangle for the ASR. Then the car died. It turned back on and died again.

Pulled codes and they were IAT sensor, CAN data interrupted, NSS, CAN fuses, and CKP magnets not recognized. I cleared the codes drove it again, hit a dip and the car died. Tried pulling codes again with no luck. Which way should I look? Fuel pump? Fuel pump relay? Lower Harness? Please let me know what you think.

 

[Joncf]

Not sure about the codes, but the symptoms almost remind me of voltage regulator failure. Whether or not that’s the problem, it might still be a good idea to replace it since the car has over 150Kmi.. if it hasn’t been done yet of course.

 

[mnessari]

Not sure about the codes, but the symptoms almost remind me of voltage regulator failure. Whether or not that’s the problem, it might still be a good idea to replace it since the car has over 150Kmi.. if it hasn’t been done yet of course.

Thank you!

Just to confirm, the voltage regulator which is behind the alternator?

 

[Joncf]

Thank you!

Just to confirm, the voltage regulator which is behind the alternator?

Yes, exactly.

 

[nocfn]

disconnect the battery before removing it.

 

[gerryvz]

Check your connections at the battery to be sure nothing is corroded, and all connections are TIGHT.

 

[gsxr]

... I cleared the codes drove it again, hit a dip and the car died. Tried pulling codes again with no luck.

What does this mean? ^^^ You could not pull codes at all, or there were no fault codes on any of the 6 powertrain modules (single blink each)?

The initial codes pulled are useless, you did the right thing by clearing all of them. You need to know if any codes are stored now since the problem recurred. Even if there are no codes at all (no faults), that does help narrow down the possibilities.

I agree with Gerry, check the battery terminals first, especially the small 10mm nut on the positive terminal. While it doesn't sounds like a harness issue, is the engine harness original or has it been replaced? Same question for fuel pumps.

Also would help if you posted the year of your 400E/E420, and if there was any work done just before this problem occurred. Looks like maybe a 1995 E420 based on other posts?

 

[mnessari]

Sorry, it is a 95 E420 with ASR. I checked my battery connections my positive terminal was on the loose side.. I unplugged, and tightened everything down, no issues yet... Fingers crossed that was the issue!