Today my 1994 E320 would not start. The engine turned over fine. The past two days the ASR light came on, but went out the next time I strated the vehicle.

I read many threads on this no start condition. One thread suggested to check the OPV Relay and the fuse, so I went out to my car and looked for the OPV. I found a 7.5 A fuse with a clear plastic cover on it near the battery. I pulled the fuse, it looked fine and I replaced it. The car then started up fine!

Is this a indication of a bad OPV relay or fuse? The fuse looks fine.

Should I replace the OPV relay anyway?

Thanks,
John

The overvoltage relay is BEHIND the large black plastic cover just behind the battery & has a BLUE 15A fuse. Sounds like you were looking at the cell phone fuse holder.

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The original OVP was so troublesome that a change to the new style is the way to go. [ short $$$ at Fast Lane]
However, as most of them have been changed by now, I would pull it and check the part # on the side. The orig will be
part # 000 540 52 45. Manufactured by Siemens. If so, replace it.

As posted, behind the black panel at rear of battery. Tall aluminum can, fuse on top. There is a hidden securing nut on the side that has to be removed .

Much Thanks, I found the OVP and the fuse per your description. The fuse is fine. The OVP appears to be the original Siemens # 000 540 52 45 so I will replace it.

FastLane has a "Overload Relay" #P2056-70038, for $58.61. Is this the Over Voltage Relay, and FastLane is just calling it Overload ? It sounds like semantics, but I hate to assume.

John

Yes, that is the one! Good luck..

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Thanks to all for your help on my OPV relay problem. I would strongly suggest if you have the orignial Siemens part #000 540 52 45 in your vehicle - replace it. It's cheep and easy to do.
I removed the battery to gain better access to the Relay. After you have removed the one retaining bolt, the relay just pulls straight off of the connector, there are not any clips etc to remove or disconnect. Take your time and wiggle the OPV from the connector.

I wish I would have done it sooner.

I wonder what other problems are probable for a 1994 E320? I recently did the Tumbler, I know about the head gasket, wiring and mount issues.

Thanks again,
John

Here are a few more.
EGR valve pipe blockage at intake
EGR valve part upgrade
Spark plug boots/resistors under coils [ 3 of them]
Rear thrust arms [ have been modified]
Start lock-out switch on trans [ suspectical to water]
Belt tension shock bushing wear [ rattle at idle]
Upping of fuse on aux fan high speed relay [ per Benz]
Right motor mound collapse [ heat ]

All pretty minor and most are DIY, if so inclined.

There are more, but these are common,,,