Can the glow plug relay drain the battery?
Thread Starter
Newbie
Joined: Dec 2009
Posts: 1
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From: Seattle, WA
1984 MB 240D
Can the glow plug relay drain the battery?
Hello, I'm brand new to the MBworld forums and to my Mercedes 240D. I have been lurking for the past few weeks and I've found that all of you are a very helpful treasure trove of knowledge. 
I have an unusual problem that I wasn't sure how to search for.
My car was behaving perfectly fine until the weather turned cold in Seattle. Then it was clear that my glow plugs were out. The glow plug light stopped working (intermittently) and the car wouldn't start. The car sat for about a week while I waited for parts to come in.
I went ahead and switched out the GPs and the GP relay today. The first time I started the car, the dash GP light came on and turned off as expected, and the car started right up.
I left the car to sit for a few hours, then when I went to drive it home tonight, it started up, but I noticed that the dash lights and headlights were dimming. I remembered that I didn't tighten the battery connections, so I pulled over and tightened them, thinking that was the problem. Then when I tried to start the car again, it wouldn't start.
I had to have the car jumped for it to start. While connected to the other battery, the GP lights came on and it started right up again. However, when I turn the car off, the process starts all over again.
The odd thing is that all the electrical systems work fine until I turn the key to engage the glow plugs. Then the lights dim and the buzzer slowly fades in volume.
Could the glow plug relay be the cause of the problem? I was thinking it might be faulty because it seems like it is draining the battery as soon as I turn the key.
Any replies would be highly appreciated, and if this has been covered, I'd love to be directed to the applicable thread.
Thanks!
I have an unusual problem that I wasn't sure how to search for.
My car was behaving perfectly fine until the weather turned cold in Seattle. Then it was clear that my glow plugs were out. The glow plug light stopped working (intermittently) and the car wouldn't start. The car sat for about a week while I waited for parts to come in.
I went ahead and switched out the GPs and the GP relay today. The first time I started the car, the dash GP light came on and turned off as expected, and the car started right up.
I left the car to sit for a few hours, then when I went to drive it home tonight, it started up, but I noticed that the dash lights and headlights were dimming. I remembered that I didn't tighten the battery connections, so I pulled over and tightened them, thinking that was the problem. Then when I tried to start the car again, it wouldn't start.
I had to have the car jumped for it to start. While connected to the other battery, the GP lights came on and it started right up again. However, when I turn the car off, the process starts all over again.
The odd thing is that all the electrical systems work fine until I turn the key to engage the glow plugs. Then the lights dim and the buzzer slowly fades in volume.
Could the glow plug relay be the cause of the problem? I was thinking it might be faulty because it seems like it is draining the battery as soon as I turn the key.
Any replies would be highly appreciated, and if this has been covered, I'd love to be directed to the applicable thread.
Thanks!
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Joined: Apr 2007
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Charge your battery
fully overnight at 10amps.Then check alternator output and battery condition.
Looks like your charging system may be the culprit.
Don't go to the dealer
I have a guy in the northend that can redo the alt. and if you need a shop to install if you don't diy I have a buddy with a shop just south of you.
I'm to busy with my own cars(putting a small block chevy and 5speed into one of a handful built in 1968 200D fintails)) this winter or I would have you come up north to Mill Creek.
Looks like your charging system may be the culprit.
Don't go to the dealer
I have a guy in the northend that can redo the alt. and if you need a shop to install if you don't diy I have a buddy with a shop just south of you.
I'm to busy with my own cars(putting a small block chevy and 5speed into one of a handful built in 1968 200D fintails)) this winter or I would have you come up north to Mill Creek.
Banned
Joined: Sep 2009
Posts: 48
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From: So CA
1984 300D,82 Volvo Diesel
For repair info on other subjects:
Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf
It is possible for an defective Glow Plug relay to Drain the Battery. If you still have the Old Relay I would try istalling that and see if it cures the prolem. Unless you know for sure your old Relay as no good.
Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf
It is possible for an defective Glow Plug relay to Drain the Battery. If you still have the Old Relay I would try istalling that and see if it cures the prolem. Unless you know for sure your old Relay as no good.
