P38A ABS FAULT AGAIN

does anyone here know of any dodgey connection areas for the abs system as i seem to be getting a lot of abs issues with the front sensors mainly, normally (short to another faults) both sensors are new
also brings up sensor electrical failure faults from time to time too
all sensors are fully pushed in and connected as they should be and sensor plugs look good,
its the later type abs ecu (99 on)
have looked at most of it the best i can without ripping it apart , do they go through any of the kick panel connectors etc or are they done in one single loom ?

Short to another sensor means the sensor is dead, bad connection or dead ecu.
The only connection is where the sensor plugs in. Straight to the ecu from there

kermit_rr said:

Short to another sensor means the sensor is dead, bad connection or dead ecu.
The only connection is where the sensor plugs in. Straight to the ecu from there

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didnt think it would be simple , does occasionally go out for a couple of minutes but it soon comes back and reminds me that it has a green oval on the front again , looks like the ecu will be out of it shortly then as i know the sensors are good

Bern768 said:

didnt think it would be simple , does occasionally go out for a couple of minutes but it soon comes back and reminds me that it has a green oval on the front again , looks like the ecu will be out of it shortly then as i know the sensors are good

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How do you know?
What resistance is there across the sensors?
What volts at the sensor plugs?

DanClarke said:

How do you know?
What resistance is there across the sensors?
What volts at the sensor plugs?

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i cant remember what ohms they tested at from the top of my head, it was yesterday i looked but they was all around the same and 3 corners show 2.3-2.5 v apart from front left which shows 0v

Bern768 said:

i cant remember what ohms they tested at from the top of my head, it was yesterday i looked but they was all around the same and 3 corners show 2.3-2.5 v apart from front left which shows 0v

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OK, so if there's 5v (or a little more) at the plug for that sensor and the sensor is measuring 0v in Nanocom the Sensor is probably FUBAR.

Been there done that. For me it is ALWAYS the OSF sensor that pops.

DanClarke said:

OK, so if there's 5v (or a little more) at the plug for that sensor and the sensor is measuring 0v in Nanocom the Sensor is probably FUBAR.

Been there done that. For me it is ALWAYS the OSF sensor that pops.

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the sensor is less than a week old ? and didnt measure any different to any of the others though, which kinda leads me to ecu or ecu wiring somewhere

Bern768 said:

the sensor is less than a week old ? and didnt measure any different to any of the others though, which kinda leads me to ecu or ecu wiring somewhere

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I had a new sensor only last a week. Still tested ok with a DVM. Another new one sorted it

kermit_rr said:

I had a new sensor only last a week. Still tested ok with a DVM. Another new one sorted it

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ah right will get the glove box apart and get to the ecu and continuity check the sensor wiring and plugs i think tomorrow just to make sure im not throwing money away fingers crossed its something there or just a sensor , dont really fancy buying a new ecu

Bern768 said:

ah right will get the glove box apart and get to the ecu and continuity check the sensor wiring and plugs i think tomorrow just to make sure im not throwing money away fingers crossed its something there or just a sensor , dont really fancy buying a new ecu

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Those Wabco-D ECU's are hideously expensive.
MartyUK on here does a repair service for the most common failure.

DanClarke said:

Those Wabco-D ECU's are hideously expensive.
MartyUK on here does a repair service for the most common failure.

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Ah right worth keeping in mind then hopefully it doesn't end up being that serious (fingers crossed) going to look at another P38 early part of next week so at least I can rotate them and have a broken one and one on the road or probably just have two broken ones lol

Bern768 said:

Ah right worth keeping in mind then hopefully it doesn't end up being that serious (fingers crossed) going to look at another P38 early part of next week so at least I can rotate them and have a broken one and one on the road or probably just have two broken ones lol

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The 2 fronts are identical so you can "easily" (a relative term) swap them across and see whether the fault moves or stays put.
Stays put its wiring /ECU, moves...its the sensor. My bet is the sensor.

WABCO-D ECU seems to be a common failure item but new sensors seem very poor quality with regular failures.

DanClarke said:

The 2 fronts are identical so you can "easily" (a relative term) swap them across and see whether the fault moves or stays put.
Stays put its wiring /ECU, moves...its the sensor. My bet is the sensor.

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You likely won't have to even try to end up with two-off VOR P38's ¦~|