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1992 400e Overload Protection Relay

Old Dec 12, 2013 | 09:51 PM
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1992 400e
1992 400e Overload Protection Relay

I've used this website for a lot of problems I've had and thought I'd give back with a simple post about a simple problem. Sorry if this has already been covered, I found mostly mixed posts and nothing this specific- though, I'm relatively new here.

Basically, I was experiencing these symptoms:

-Battery was being drained to nothing (even jumping it took time because it needed to charge a little before it'd crank up)

-ABS unit under the hood was making a clicking sound every couple of minutes after the engine was shut down (this is where the battery juice was going I assume)

-Even with the battery charged (left the car running for a couple hours) it took up to 10 seconds of cranking to get the thing to start back up even though I was starting it right after I had shut it off


-I could see sparks coming from the negative post as I touched the unattached battery cable to it while it was off and nothing electronic was on in the car (old trick to check if there's something drawing current from your battery)

After a little online research, I discovered that the clicking sound the ABS was making can be caused by a faulty overload protection relay (OVP). So, I went and took a look at the two fuses and they seemed fine. I could see that there was water and condensation inside the hood that covers the fuses, though.

So, I decided to buy a cheap one online and see if it made any difference (sorry purists, I got the Uro brand one for $25 including shipping at autohausAZ- I will get a better one when I can afford one). I received it in the mail today and VOILA! Engine started like a charm! There were no longer sparks coming from the negative post when I tried the above mentioned trick and there were no longer clicking sounds coming from the ABS.

I was so relieved. According to my research, it could have been any number of more expensive problems. I'm so glad it was this easy. Anyway, I cracked open the old Overload Protection Relay and well... have a look:


Rusty water leaked out when I turned it upside down!


Yuck!


Yes, that's ice. It was freezing outside but I just couldn't wait to put the new one in. Obviously water had made its way passed the deteriorating seals and had been sitting and corroding for years. The lesson here is probably that you shouldn't just trust the two fuses and assume it's fine if they aren't blown. Cheers!

Last edited by My400e; Dec 12, 2013 at 10:10 PM.
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