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W163 and General M Gremlin
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Discussion Starter · #1 · (Edited)
As I'm not an electrical wiz with these w124s,
Can anyone tell me what the relationship is, if ANY, with fuse #5 and relay F (convenience relay - part # A0015427819)
Relay was clicking on and off, when I went to unlock the car this morning. I noted last night when locking it up, only the Front DS door locked, the others did not - manually locked up the other doors for the night and to investigate later.
This morning opened up front DS door, to hear a relay clicking behind the dash. Checked under the hood, opened the fuse relay lids and found this clicking away, F fuse - convenience relay

Now, I have an ongoing Fuse #5 blow out I'm still TSing (blows out when the break pedal is depressed) - sounds like a ground fault somewhere.

With the F Relay clicking, I thought this was perhaps related to the fuse blow out. I pulled fuse 5 out and the F relay clicking stopped. Reinstalled fuse 5 and no more clicking.

Another electrical gremlin.

Screen Shot 2021-07-18 at 12.05.46 PM.png


UPDATE:
Nothing to do with fuse 5.
Clicking came back with fuse 5 in or out.
Surmising it has to do with the cluster out and N2/4 presently disconnected.
Relay F tied to Fuse C.

Screen Shot 2021-07-18 at 10.46.05 AM.png Screen Shot 2021-07-18 at 2.41.57 PM.png

I'll figure this out.
 

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W124
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5,825 Posts
As I'm not an electrical wiz with these w124s,
Can anyone tell me what the relationship is, if ANY, with fuse #5 and relay F (convenience relay - part # A0015427819)
Relay was clicking on and off, when I went to unlock the car this morning. I noted last night when locking it up, only the Front DS door locked, the others did not - manually locked up the other doors for the night and to investigate later.
This morning opened up front DS door, to hear a relay clicking behind the dash. Checked under the hood, opened the fuse relay lids and found this clicking away, F fuse - convenience relay

Now, I have an ongoing Fuse #5 blow out I'm still TSing (blows out when the break pedal is depressed) - sounds like a ground fault somewhere.

With the F Relay clicking, I thought this was perhaps related to the fuse blow out. I pulled fuse 5 out and the F relay clicking stopped. Reinstalled fuse 5 and no more clicking.

Another electrical gremlin.

View attachment 2702573


UPDATE:
Nothing to do with fuse 5.
Clicking came back with fuse 5 in or out.
Surmising it has to do with the cluster out and N2/4 presently disconnected.
Relay F tied to Fuse C.

View attachment 2702595 View attachment 2702596

I'll figure this out.
Possibly a wire broken in the loom between the door and the chassis. Frequent opening and closing of the driver's door can literally break the wires inside the loom and possibly short them.
 

W163 and General M Gremlin
Joined
7,644 Posts
Discussion Starter · #3 ·
Possibly a wire broken in the loom between the door and the chassis. Frequent opening and closing of the driver's door can literally break the wires inside the loom and possibly short them.
Appreciate the reply, Sir.
With the cluster out, I've run continuity tests on the puddle wiring 2 door switch, door switch to pin 7 on the harness to the N2/4 (open and closed the switch to test) - all good.
I do have the cluster out right now, as well as disconnected the brake light switch below (disconnected only the bigger 2 prong connector on it), as it was blowing fuse #5 every time it was depressed.
N2/4 module pin 7 trace was fried but got that fixed with an added trace (have a spare, if needed)
Waiting for a BLS to arrive - I tested the BLS for continuity - it was operating as required, but Im not 100% sure if it is causing the ground fault, hence, test with a known good one.

With the relay F clicking, I pulled each fuse out to test. Fuse C is tied to the 'F relay'. Pulling it shut down the relay clicking on and off. Waited a minute and re-installed. It's been quite for the last 2 hours.
 
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