10 replies to this topic

[DavidB]

I’ve had the ABS light on since I bought my VX220.
I had a look and the blue wire just before the plug has broken. I installed a new connector, but ever since reconnecting this, I’m getting TPS failure EML multiple times until I just unplug it. Pedal doesn’t do anything, and idle is very lumpy.

I’m wondering if previous owner just clipped it and said it’s just a broken wire knowing it has another problem (he did this with a few other things as well). My Delphi diagnostics recognised RR as the faulty ABS sensor - plugging it in doesn’t remove the code (P1221), even after clearing it.

What is the deal with this? I’m not sure if this is connected (no pun intended) but the battery was dead after running for a few minutes and dashboard stuff spazzed out. I bought a new battery this morning (previous owner said ‘battery was new!’, receipt shows new in 2023 and it looks OLD, even installing a kill switch to stop the alarm draining OLD and KNACKERED battery - too cheap to buy a new one) and everything is fine, apart from disconnected RR sensor and impending TPS fault if I plug it back in.

Edited by DavidB, 24 May 2025 - 06:09 PM.

[stevieturbo]

Throttle position has absolutely nothing  to do with the ABS. The cars are renowned for wiring/corrosion/connector issues though which might relate to the TPS. But again, view/record live data to see where any anomalies lie

 

As for the ABS, view live data to see which wheel is not offering sensible data. Or scope each wheel sensor for a valid signal

[DavidB]

I wonder why it keeps giving me this error with the TPS everytime it's reconnected ... ?

 

I've used it for the past two days (and every other day) and it's been fine, as soon as it's bridged, I get at least five TPS "Throttle Position Sensor 1-2 Performance" fault codes every hour and dead throttle pedal until I restart.

Edited by DavidB, 25 May 2025 - 10:06 AM.

[Ivor]

I wonder why it keeps giving me this error with the TPS everytime it's reconnected ... ?

I've used it for the past two days (and every other day) and it's been fine, as soon as it's bridged, I get at least five TPS "Throttle Position Sensor 1-2 Performance" fault codes every hour and dead throttle pedal until I restart.

Sounds like crossed wires to me...

[hairy]

Loom of doom

[stevieturbo]

I wonder why it keeps giving me this error with the TPS everytime it's reconnected ... ?

 

I've used it for the past two days (and every other day) and it's been fine, as soon as it's bridged, I get at least five TPS "Throttle Position Sensor 1-2 Performance" fault codes every hour and dead throttle pedal until I restart.

 

 

What do you mean, " as soon as it's bridged" ?

 

ABS sensors in no way whatsoever interact with engine wiring. They run direct from each wheel to the ABS unit only.

[Ivor]

I wonder why it keeps giving me this error with the TPS everytime it's reconnected ... ?

I've used it for the past two days (and every other day) and it's been fine, as soon as it's bridged, I get at least five TPS "Throttle Position Sensor 1-2 Performance" fault codes every hour and dead throttle pedal until I restart.

What do you mean, " as soon as it's bridged" ?

ABS sensors in no way whatsoever interact with engine wiring. They run direct from each wheel to the ABS unit only.

Unless there's a crossed wire or corroded plug, or previous owner rewired a loom plug incorrectly? I guess the start is to follow the abs wire from the wheel to the abs unit and check any plugs along the way ?

[stevieturbo]

Of course yes, anyone could have done anything in the past.

 

But they ABS wheel wiring goes direct from wheel to ABS unit, they do not pass through any other connectors along the way as far as I'm aware. So it should be really really difficult for someone to screw that up.

 

Again, simple investigation of the relevant signals would be the first port of call.

 

Scope/log the wheel speed outputs and the throttle for any anomalies.

[Ivor]

Of course yes, anyone could have done anything in the past.

But they ABS wheel wiring goes direct from wheel to ABS unit, they do not pass through any other connectors along the way as far as I'm aware. So it should be really really difficult for someone to screw that up.

Again, simple investigation of the relevant signals would be the first port of call.

Scope/log the wheel speed outputs and the throttle for any anomalies.

Good info

[peteslag]

Disconnect the large plug from the ABS ECU - measure the electrical resistance between the following pins plug-side (to the wheels!): 9+10 (rear right wheelspeed sensor) 12+13 (front right) 22+23 (rear left) 14+25 (rear front) - each pair should read a resistance of 1,4...1,7 kOhm 

 

If you get a reading from your RR sensor that is different to the rest then that is a sure sign that you have a wiring problem.

[Ivor]

Disconnect the large plug from the ABS ECU - measure the electrical resistance between the following pins plug-side (to the wheels!): 9+10 (rear right wheelspeed sensor) 12+13 (front right) 22+23 (rear left) 14+25 (rear front) - each pair should read a resistance of 1,4...1,7 kOhm

If you get a reading from your RR sensor that is different to the rest then that is a sure sign that you have a wiring problem.

Assuming rear front should read front left ?