Overvoltage protection relay. A search will find thousands of threads...literally.

The ABS light on is #1 sign its toast. Get a new one and put that at rest.

Car being hard to start is another one. If the car starts quickly the OVP is probably fine.

Unfortunately not always. Both my cars did not exhibit poor starting, yet the OVP was dead. If the light is on and the ABS does work, replace it.

Guess I will go look at that now. Thanks! This is located behind the battery correct?

Went out to check it.. Yup fuse is blown, replaced that and the ABS light is gone WOO HOO! She idles a little better also, still have some work to get it smooth though.


So I have another question, my temp gauge inside the car is black or reads 136. When I first start it up it drops from 136 down to 111 and climbs back before going blank. Is that the computer going out or ?

Good.

I personally would still replace the unit since it happens to every 124 regardless. Just because the fuse isn't blown doesn't mean the relay is perfect. Microfractures in the solder occur just the same as it does in the cruise control relay/amplifier, the multipurpose + combination relay etc...It's the age that does it.

Just replace it and have peace of mind. My 2c.

Ps2cho, I'll grant that in the ideal weather that you enjoy in the O.C., an M103 will start fairly easily even with a non-functioning OVP, but in most other places, especially when the weather is cooler, the car will be harder to start.

And when are you finally gonna make it to one of our drag racing days?

Colorado220, was your car harder to start before you replaced the fuse? What were the weather conditions? Glad things are working good.

I like the peace of mind of keeping my money where it belongs (in my pocket) and only spending it when necessary. ABS light gone, easy starting and running good equals good OVP. If it ain't broke, don't fix it. I replaced only the fuse in my 89's OVP last fall to cure it's hard starting issue and the car is still running like a top to this day. Spend your money where it's needed, on the car's other issues and save the rest for a rainy day.
Regards, Eric

It took a little bit to start before, yes. Weather has been hot/humid (for me anyways) low 90's with periodic short t-storms. And I am all for keeping $$ in my pockets. I am trying to fix as much as possible with what I already have. I will start to scour the scrap yards soon.

your temp gauge issue might be from your outside temp sensor. check to see if it was damaged from whatever hit the grill etc. Check if this sensor was pinched. if your car is like mine, that sensor is behind your front license plate

That is where I am going to look first. I just thought I would ask.

Did some more on the Benz today. New belt, new tension adjuster( man that was a PITA), cleaned front of the motor (turns out that it's not black under there LOL), and a quick oil change. Also looked into fixing the tear in the rear roof.. Found an arrow up there... What else is hidden is this car? LOL

I also was wondering how to test the AC compressor real quick. Is there a way to get the compressor to spin under the hood as a quick test? Just want to know before I go on Thanks

I have another question however, what is the piece mounted to the exhaust? My guess is smog??
http://i256.photobucket.com/albums/h...E/DSCN2750.jpg

EGR valve

Put a can of freon into your ac, if the pressure is low, ac compressor will not run (to prevent damage to the compressor) .....

"Freon" is a possible problem here. I think a 90 is still an R12 car if it hasn't been converted to a newer refrigerant yet. Don't just throw a can of refrigerant in until you know what the car needs.There are differences in the fittings to prevent mixing the two but sometimes people put an adapter fitting on without doing a proper conversion to a newer refrigerant. R134a and R12 are not compatible and some of the "substitutes" for R12 are junk and will cause you trouble. There are many who believe that all of the "substitutes" are junk. I've just been doing without air cond rather than deal with the headache.
Regards, Eric

Never had a car with AC, thought I might give it a try.

Hmm.. I am used to domestics where the EGR is on the back of the block near the firewall. Thanks