w126 SRS ABS Light on, RPM Gauge Spiking, Radio Stops, AC Stops, Headlights dim - PeachParts Mercedes-Benz Forum

geminichrisw126 · #1 04-25-2010, 12:52 AM

OK, I have an 1989 420sel with 141k miles on it. The car has been perfect until the rains came to Colorado this past week. I got gas, left the gas station, turned on my windshield wipers and the headlights. My car started to fog up on the inside, so I turned on my deforster. All of a sudden the radio cut out and the climate control system stopped working and I noticed the SRS and ABS indicator lights were lit. My lights dimmed and my rpm gauge went hay wire. I drove the 4 miles to my house and turned the car off. The rain stopped and I decided to see if "hopefull", yet stupidly, the problem had fixed itself. The car drove fine for a mile, then the problem started up again. I returned home, let the car sit for a few hours, NOW the Battery is dead.

Long Story short, I researched online and it sounded like the Over Voltage Protection Relay or OVP relay. I bought a used but working one this morning. I took the old one out and replaced it. I charged the battery. The car seemed to be working fine. I drove for thirty minutes and the lights dimmed, srs and abs lights lit, radio went off, and the windows were slow to roll up. Got back online. Sounded like the Alternator, bought an alternator, installed it, charged the battery, did voltage tests, and every thing seemed to be fine.

Decided to go for one more drive. THE CAR DROVE PERFECTLY, the best ever for 45 minutes, then, lights dimmed, srs and abs light came back on, radio turned off as well as the heater. ANY IDEAS. ???? I have already spent 200 bucks on this today, and I am hoping I do not get the pleasure of purchasing a battery tomorrow?

ANY HELP WOULD BE GREAT!
Researched online.

JohnM. · #2 04-25-2010, 05:00 PM

Sounds like a battery failing under load. You can go to any auto parts store, bring your battery inside, and they will load test your battery for free. So your not throwing anymore parts/$$$ at it.

kiwi_bloke_nz · #3 04-26-2010, 04:56 AM

I agree, it was lack of voltage. Had this with a 190E.

Like mentioned above. Test the battery and test that it is charging while the car is running.

tinypanzer · #4 04-26-2010, 10:40 PM

Also make sure your battery terminals aren't suffering from corrosion.

mbdoc · #5 04-27-2010, 08:17 AM

IF the battery tests good?? most likely the voltage regulator OR alternator.

tinypanzer · #6 04-27-2010, 05:00 PM

That's what I thought too, Doc, but he says he's already put a new alternator on it, and I assume that would come with a new voltage regulator too, eh?

geminichrisw126 · #7 05-08-2010, 12:13 AM

Thanks for the help guys... SO i put in a new OVP and Altenator. I had to go out of town, and I got back yesterday. I bought a new battery today, and it was perfect. Now, the problem seems worse. I drove for about 2 hours, then very rapidly, the srs abs light came on, radio and air out, headlights went off, no lights. I normally had plenty of time to get home, but this time I had to keep turning the headlights off to keep the car from stalling. It is parked at a grocery store about 2 miles from my house and I am charging the brand new battery.

SO, I have replaced the Battery, ALternator, and OVP? Any one have an ideas? I am pretty fustrated right now.

geminichrisw126 · #8 05-08-2010, 12:16 AM

Could it possibly be bad cables from the alternator to the battery?

geminichrisw126 · #9 05-15-2010, 12:57 PM

I FOUND THE PROBLEM... I was sold a bad alternator. I am not sure if it was the OVP, the battery, or the alternator, but all three are changed and it works GREAT!

d.delano · #10 05-15-2010, 01:04 PM

You know you probably could have just bought a new voltage regulator and saved yourself a whole lot of trouble. That would have been the very first suspect had it been me with your problems. Easier than checking the air in your tires to replace.

geminichrisw126 · #11 05-28-2010, 01:12 PM

I finally figured it out. You were all sort of correct. The auto parts store sold me a bad alternator. Problem solved!

tinypanzer · #12 05-28-2010, 10:30 PM

Hah, MBDOC was right again! I have no idea if he read the part where the guy said he bought a new alternator or not, he certainly gets extra credit if he did read that part and still called bad alternator!