Dreaded ASR light on again ?

Quick Silver

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I think I need some good brains on this one .

On my 300 SL (Straight Six) which I've had for 3 years now I've had a problem with the ASR light coming on .

When I first got the car I replaced the ignition switch because it was extremely stiff (a Well known fault) and all was fine for 6 months or so .

Then I started getting the ASR light on frequently so I replaced the the OVP relay and the brake light switch and all was fine .

Then after a long period of being laid up for the winter this year (4 months) .
When I came to use the car again it barely turned over and fired due to low battery voltage and the ASR light was on untill the battery had a decent charge into it after a run the ASR light went out after the car was restarted and has been fine ever since .

Untill.........Last week when the ASR light came on and remained on for over 2 days even though the battery was fully charged . The car was in limp home mode and the cruise control was inoperative and a stiff accelerator pedal (Normal behavior if there is a problem).

Then ......All of a sudden the car returned to normal (no stiff throttle and cruise control working as normal) yet the the ASR light remained on untill I stopped the engine and restarted it then all was normal with light extinguished and it has been OK ever since .

I am really baffled by this as really cant point the finger at any thing in particular .

My car doesn't have full diagnostics only partial as It's a 1990 model (129) and it has only a single speed sensor on the Differential .

Mark Mifsud is bringing his star diagnostics to our Essex GTG @ Runwell this weekend and is going to see if we can find what is going on but would like a few pointers as where to look to try and eliminate the problem .

All Ideas greatly appreciated as this is really bugging me now.

I'm off to work now so hopefully read your replies when I finish around 2AM .

Chris.
 

television

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I will have to round you up all of the links that I have.

I got about 5 good ones for jay when his 126 ASR went down
 
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Quick Silver

Quick Silver

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R129 1990 SL 300..
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i think i need some good brains on this one .

On my 300 sl (straight six) which i've had for 3 years now i've had a problem with the asr light coming on .

When i first got the car i replaced the ignition switch because it was extremely stiff (a well known fault) and all was fine for 6 months or so .

Then i started getting the asr light on frequently so i replaced the the ovp relay and the brake light switch and all was fine .

Then after a long period of being laid up for the winter this year (4 months) .
When i came to use the car again it barely turned over and fired due to low battery voltage and the asr light was on untill the battery had a decent charge into it after a run the asr light went out after the car was restarted and has been fine ever since .

Untill.........last week when the asr light came on and remained on for over 2 days even though the battery was fully charged . The car was in limp home mode and the cruise control was inoperative and a stiff accelerator pedal (normal behavior if there is a problem).

Then ......all of a sudden the car returned to normal (no stiff throttle and cruise control working as normal) yet the the asr light remained on untill i stopped the engine and restarted it then all was normal with light extinguished and it has been ok ever since .

I am really baffled by this as really cant point the finger at any thing in particular .

My car doesn't have full diagnostics only partial as it's a 1990 model (129) and it has only a single speed sensor on the differential .

Mark mifsud is bringing his star diagnostics to our essex gtg @ runwell this weekend and is going to see if we can find what is going on but would like a few pointers as where to look to try and eliminate the problem .

All ideas greatly appreciated as this is really bugging me now.

I'm off to work now so hopefully read your replies when i finish around 2am .

Chris.



bump bump bump
 

television

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I have not forgotten and I will print out tonight what I can find..

This is the hardest fault to find on any car
 

television

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I have sent you 4 stock ASR papers not especially for you car, but the principle is the same for now
 
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Quick Silver

Quick Silver

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Very useful Malcom thanks , I've discovered one thing that doesn't seem quite from reading the papers .

The SNOW CHAIN SWITCH ?
I've never used this but what I've discovered is that the red light on the switch comes on when you turn the ignition on and goes off when the engine is running which is fine BUT, when you operate the switch nothing happens and no red light when the car is stationary with the engine running or if you operate the swich whist the car is being driven.

I've just tried making the rears wheels slip on some wet grass and the orange triangle light comes on which is at the top of the speedo again this is fine .
 

television

Always remembered RIP
Joined
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2002 SL500, 216 CL500, all fully loaded
I have made a note of your post, and will find somethings for specific
 


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