FIXED - C2 ABS ESC Speedo problem (U0122, P0501)

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wheeler
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by wheeler »

Best off to get a new plug with a good length of wire from a scrapyard, you can remove the individual terminals from the connector & only replace what you need too. You would likley need to replace the complete harness if not doing this.

You wont get any AC voltage from the wheel speed sensors as they are not inductive, they ate a kind of Hall effect sensor & generate a square wave signal.

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myglaren
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by myglaren »

If you can't source a connector, you may be able to replace the pins in the damaged one - RS Components, Farnell and Mouser are good for such items.

amallaburn
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by amallaburn »

How do I open this up to view other side of connectors?
Last edited by amallaburn on 13 Feb 2021, 21:25, edited 1 time in total.

wheeler
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by wheeler »

Remove the locking clip first, it will only come off in one position.
Remove the top cover, there are 2 locking tabs you need to carefully push out then it slides off.
On the short side there is a an insert that has to be pulled out.
You then need to insert something very fine (I use a small safety pin) in the hole next to the terminal then you can pull out the wire & terminal.
I will try & add pics as it can be hard to explain this.

Its not the exact same plug but its the same idea.
plug1.jpg
plug1.jpg (13.84 KiB) Viewed 68 times
plug2.jpg
plug2.jpg (20.18 KiB) Viewed 68 times

amallaburn
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by amallaburn »

The female pins look ok on plug, the male one needs repaired in socket, how is the PSF/BSM board removed and opened?

Must be a common PSA fault

amallaburn
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Removing BSM

Post by amallaburn »

Is there a knack to removing this connector, couldn't seem to get it off when trying to disconnect BSM
aaaaaa.jpg

ozvtr
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by ozvtr »

Locking tab is the same as the big black one. Just keep trying.

Pin 19 of brown receptacle is power from fuse F9.

amallaburn
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by amallaburn »

Thank you Ozvtr, do you know how I can take board apart?

ozvtr
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Re: C2 ABS ESC SPEEDO problem (U0122, P0501)

Post by ozvtr »

The photos are the tabs for a BSI but the BSM (PSF) is similar.

Use a sharp knife and cut through any labels along the separation line of the upper and bottom halves.

I have a tool from a door panel removal kit that does this job. A screwdriver will work but some thing sharp is better.

Be careful, the tabs can be easily broken.
tool 001.jpg
tool 002.jpg
tabs.jpg
Unfortunately yours is a MK2 and the upper part of the BSM is potted in a resin. So there isn't much you can do with it.

amallaburn
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Thank You

Post by amallaburn »

Took the fuse box out today, tried opening was close to smashing it with hammer at one point, so didn't bother - they do not like to be opened, one side felt glued down.

Instead I have done a temporary fix until new (used) fuse board arrives.
ozvtr wrote:
13 Feb 2021, 23:14
Pin 19 of brown receptacle is power from fuse F9.
I checked for continuity between various pins and the fuse holders (I removed all fuses), they all seemed to be connected at top of fuses. I took the Fuse F9 (10A) and soldered a wire to the top side (pin closest to the connectors at back of fuse board).

I have cut the Orange cable going to PIN 19 on the Brown 28 Way connector and connected this to the wire I soldered on to Fuse F9 to bypass the connector

Started the car up, ZERO problems (other than a coolant problem which has only been present since mechanic replaced steering rack, which I'll start new thread for)

Wiped codes in Lexia, only faults showing now are radio related (because an aftermarket one is in)

Thank you to Ozvtr, Wheeler and GiveMeABReak
Attachments
fuseyyyy.png

amallaburn
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Re: FIXED - C2 ABS ESC Speedo problem (U0122, P0501)

Post by amallaburn »

Just bringing this back up

After finding information online about many PSA cars having a water ingress problem in the fuse box (PSF1), is there any sort of recall for this fault?

Replacing the engine bay fuse board but surely this problem will keep occurring if it is happening from some sort of capillary action.