electrical issues - relay failures?
Thread Starter
Junior Member
Joined: Sep 2004
Posts: 31
Likes: 0
From: Charlottesville, VA
2008 E320 Bluetec / 1994 e420 (totaled) / 1997 SL500 / 1991 300SE / 1991 300e 2.6 (sold)
electrical issues - relay failures?
Hello,
Hoping someone might be able to lead me in the right direction with the issues I am having on my '91 300e 2.6.
Noticed the fuel, temp, and oil pressure gauges, as well as the tachometer quit working, as well as possibly some of the warning lights. The speedometer still works, as do the exterior lights/instrument panel lighting. There is a buzzing noise coming from the fuse/relay box area. This buzz goes away when you use the turn signal stalk, or activate the hazard warning switch. All fuses seem to be in good condition.
I replaced two of the relays, first the "exterior lamp failure monitoring unit" since I was told it seemed to be related to the issue, still heard buzzing and didn't fix the issue, but the buzzing seemed and felt to come from the "combination relay", so replaced that one as well and got the noise to go away, as well as having the gauges work. However this lasted just a few seconds, and then the buzzing returned, as well as the non functioning of the instruments.
Any thoughts if failure of one relay could "blow" out another? Should I replace them both at the same time? Any other thoughts? Thanks for your help!!!
Hoping someone might be able to lead me in the right direction with the issues I am having on my '91 300e 2.6.
Noticed the fuel, temp, and oil pressure gauges, as well as the tachometer quit working, as well as possibly some of the warning lights. The speedometer still works, as do the exterior lights/instrument panel lighting. There is a buzzing noise coming from the fuse/relay box area. This buzz goes away when you use the turn signal stalk, or activate the hazard warning switch. All fuses seem to be in good condition.
I replaced two of the relays, first the "exterior lamp failure monitoring unit" since I was told it seemed to be related to the issue, still heard buzzing and didn't fix the issue, but the buzzing seemed and felt to come from the "combination relay", so replaced that one as well and got the noise to go away, as well as having the gauges work. However this lasted just a few seconds, and then the buzzing returned, as well as the non functioning of the instruments.
Any thoughts if failure of one relay could "blow" out another? Should I replace them both at the same time? Any other thoughts? Thanks for your help!!!
Last edited by cho260e; Sep 16, 2004 at 11:14 AM. Reason: add'l info
Senior Member
Joined: Aug 2004
Posts: 263
Likes: 11
BMW E30. I've turned to the dark side.
its kinda difficult since the car is not in front of me, but it sounds like the fuse box may be your problem. maybe have some one in the car and watching the gauges, while wiggling the fuse areas. or even the fuses will crack and look okay but will not allow current through, sometimes they will just corrode where they make contact. HTH
Thread Starter
Junior Member
Joined: Sep 2004
Posts: 31
Likes: 0
From: Charlottesville, VA
2008 E320 Bluetec / 1994 e420 (totaled) / 1997 SL500 / 1991 300SE / 1991 300e 2.6 (sold)
electrical issue - relays? - fixed!!!
Thank for the reply, finally think I fixed it by replacing all the fuses in the box with new. It looked like they were all original and some were so brittle they broke as I pulled them.
