Mercedes-Benz Forum banner

1 - 20 of 25 Posts

·
Registered
1982 240D & 1997 E300
Joined
·
24 Posts
Discussion Starter #1
A while back my SRS light came on right around the time I placed a heavy bag of groceries on the passenger seat so I assumed that the wires on the sensor in the seat had finally failed. A few days later some numpty performed a creative maneuver in front of me and when I went to toot my horn there was no response. Hmm! SRS and no horn, could it be the clock spring that I did not treat very well when I repaired the loose stalks last year has finally given up? Checked upper horn and it is not getting juice. Ran Carsoft 7.4 and got an error for the driver’s airbag squid ignition…

Does anyone know of a way to test a clock spring? When I was fixing the stalk problem I gave the clock spring a pretty good rogering in an attempt to disconnect one of the connectors that is not meant to be disconnected, so I am willing to believe that the clock spring has failed, though I would like to be able to test the clock spring before I spend the $90 for a new one. Thanks!
 

·
Banned
1999 E300 TD
Joined
·
2,045 Posts
What about checking the voltage at the horn relay------what happens to the circuit, that the relay is in when, you depress the spring??
 

·
Registered
1982 240D & 1997 E300
Joined
·
24 Posts
Discussion Starter #3
Faulty clock spring

Turns out it was a duff clock spring. No obvious problems with the cable or connectors on the clock spring. Once the new unit was installed the SRS light stayed illuminated until I used Carsoft to clear the airbag codes. Nothing like an impending state safety inspection to make me address this issue to repair my horn.
 

·
Registered
Joined
·
1 Posts
Hi Guys, a class problem with srs light, scanner says airbag ignition circuit faulty(4) side ignition circuit l-front faulty(8) and finally side ignition circuit r-front faulty(9), am using a solus but no c,b or p codes coming up, just that description? any ideas?? cheers from the uk!
 

·
Registered
300SEL 6.3 (1972), 300E (1990), C280 (1994)
Joined
·
196 Posts
I have same problem, first my horns began weird and stopped working, I could toot them rarely. And after next start of the engine, the SRS light remained on. I scanned the car : Airbag ignition circuit driver, erased the code and light went off and I could blew horns. After first turn horns stopped working but SRS light remained off.
I guess it is probably a bad contact in clock spring, what do you think?
 

·
Registered
2005 ML 350
Joined
·
17 Posts
There may be another post that covers my issue but related to this issue. First problem was horn started coming on while turning the steering wheel. It got continually worse to the point I was not drivable. I removed the fuse and got back on the road. A few days later I started to fix the horn and found threads to get to the problem After removing steering wheel airbag I reconnected battery to test horn. The horn problem was solved by replacing the insulating washers between the 2 metal bar that activate the horn circuit when you push in on airbag.. Before I solved the horn problem i tugged on the wires coming from clock spring and tried to loosen the 4 small screws holding steering wheel to flange that slides on to steering column.
Now my SRS light wont go out and not sure if my C reader II scan tool can reset it.
Most likely I have to remove steering wheel and inspect clock spring for damage.
Any advice here would be very welcome.
2005 ml 350 special edition
 

·
W210 Section Moderator
1998 E320 base sedan @ 160kmiles
Joined
·
8,175 Posts
Have you connected the battery to test the horn with airbag left disconnected ? That may be the cause.
..
Regarding the scanner, you can try Autel AP200M dongle, or Foxwell NT530. Not familiar with the SRS for your ML350
 

·
Registered
2005 ML 350
Joined
·
17 Posts
Have you connected the battery to test the horn with airbag left disconnected ? That may be the cause.
..
Regarding the scanner, you can try Autel AP200M dongle, or Foxwell NT530. Not familiar with the SRS for your ML350
Yes I was focused on fixing horn. During the process the power was reconnected with air bag disconnect. I didn’t realize that would create a fault. I’m inclined to believe I have a faulty component because some other thread said it should clear itself if everything is ok. The reason I suspect the clock spring as it was right there during horn repair.
thanks for the tip on scanners but I read the box on mine and it says will reset STS on some models. I’ll check out the onesyou mentioned thanks
 

·
W210 Section Moderator
1998 E320 base sedan @ 160kmiles
Joined
·
8,175 Posts
I do not believe the airbag fault code will clear itself. It has to be cleared by a scanner. It is correct that the passenger seat occupancy SRS code will clear itself if the condition that causes it no longer there.

The best way to find out is to use your scanner and check if it can access the fault code, and clear it. Else you either try different scanners, or take it to an auto shop and have them clear it. If the code cannot be cleared by a scanner capable to clear the code, that means the fault is persisting, and then you can check the connections at the clock spring.
 

·
Registered
2005 ML 350
Joined
·
17 Posts
Have you connected the battery to test the horn with airbag left disconnected ? That may be the cause.
..
Regarding the scanner, you can try Autel AP200M dongle, or Foxwell NT530. Not familiar with the SRS for your ML350
I wonder if it’s possible to have horn work with bad clock spring. Maybe only the airbag wires are affected. I saw on one pass thru the scanner that there was short to ground
And a different fault said short to positive. Is clock spring just ribbon cable? Could not repeat faults after unsuccessful clear.
 

·
W210 Section Moderator
1998 E320 base sedan @ 160kmiles
Joined
·
8,175 Posts
It is just a ribbon cable. You need to go by the fault codes, rather than the generic scanner's translation of the fault code(s). The MB SDS equipment is the golden standard, as it is brand specific.

I had an SRS light and I scanned it with a scanner I had (not Autel). It provided the fault code, and the interpretation said it was the "driver's airbag squib". When I looked up the fault code in the MB document, it was for the passenger seat sensor. I knew that was the problem and it was confirmed by the MB document. The scanner cleared the code with no problems though.

You need to scan the SRS module, and obtain the code(s) and post them here.
 

·
Registered
2005 ML 350
Joined
·
17 Posts
C05B3AE2-18D5-47CB-8864-2771B50912E5.jpeg
E57A1356-571B-460E-99A6-2139A702386F.jpeg
It is just a ribbon cable. You need to go by the fault codes, rather than the generic scanner's translation of the fault code(s). The MB SDS equipment is the golden standard, as it is brand specific.

I had an SRS light and I scanned it with a scanner I had (not Autel). It provided the fault code, and the interpretation said it was the "driver's airbag squib". When I looked up the fault code in the MB document, it was for the passenger seat sensor. I knew that was the problem and it was confirmed by the MB document. The scanner cleared the code with no problems though.

You need to scan the SRS module, and obtain the code(s) and post them here.
2677406

2677407
 

·
W210 Section Moderator
1998 E320 base sedan @ 160kmiles
Joined
·
8,175 Posts
I sent screen shots of the data stream. Could not communicate with ECU TO SEE FAULTS
My neck is killing me bending my head sideways reading the screens :). I guess it is good for the flex exercise :).

It appears that you have more than a single code for the airbags and safety belt tensioners. For example it says you have a problem with passenger airbag squib which of course has nothing to do with the clock spring. It looks like you have a wiring / connectorization issue with the Airbag module itself.

Can your scanner access the Airbag module ?

This is for 2005 ML350, right ? This is the W210 forum, so the airbag codes applicable for the W210 system start with BXXXX. For example driver's airbag squib fault code is B1859.
 

·
Registered
2005 ML 350
Joined
·
17 Posts
My neck is killing me bending my head sideways reading the screens :). I guess it is good for the flex exercise :).

It appears that you have more than a single code for the airbags and safety belt tensioners. For example it says you have a problem with passenger airbag squib which of course has nothing to do with the clock spring. It looks like you have a wiring / connectorization issue with the Airbag module itself.

Can your scanner access the Airbag module ?

This is for 2005 ML350, right ? This is the W210 forum, so the airbag codes applicable for the W210 system start with BXXXX. For example driver's airbag squib fault code is B1859.
It’s 2005 ml 350. Everything was fine till I disconnected the driver airbag??
I’m not sure I was only able to see data stream. When I looked for faults I got message that couldn’t communicate with ECU
 

·
W210 Section Moderator
1998 E320 base sedan @ 160kmiles
Joined
·
8,175 Posts
Can you read the vehicle information after you select Benz ?
Have you tried scanning any other vehicle with the Creader scanner you have ?
Have you tried scanning with the Engine started ?
I believe you need to sort the scanner issue out first. You should be able to access the ECU first and any other module after that. You said you cleared the Airbag codes and they came back ? How did you do that ? Or did I misunderstand ?
 
1 - 20 of 25 Posts
Top