Wazagadoo

New Member
Hi everyone,

I need some help.

I've just got my P38 back from a "landrover specialist" after over 3 months, long story, but they were changed the wheel bearings and fixed the head gasket, but buggered the electrics and ended removing my LPG system along the way.

Anyway, now its showing ABS Fault & Traction Control faults. The ABS seems to be working (its stops anyway), but I'm not sure how I know if the pump etc is all working correctly. I've seen posts about the pumps and relays, but how do I know if the pump is working and which relay or switch is it?

The brake lights are working fine.

As they changed the bearing is there a good chance its just the sensor? If so how do I check the sensor?

Also, does anyone know what is supposed to be in the compartment next to the battery? The cover is now missing, but as I've never paid much attention before I don't know if there ever was anything in there!

Many thanks
 
If the pump isn't working....you won't have any discernible braking effect.....

In the black box behind the battery is supposed to be the engine ECU!!!!!

You need to either a) give it back to them and threaten to sue.....b) tell them you will get it fixed properly by proper mechanics and send them the bill......c) get it fixed yourself using a reputable place and never don their door again and let us all know who they were so we can steer clear.

Diagnostics is needed to see why the lamps are on.....they do come on when battery volts drops...so check this also.
 
Trying to remove the hubs without first removing the ABS sensor does not do them a lot of good. Maybe they damaged them and just stuck them back in. Sound like a set of comedians to me. Brakes working is not the same as ABS working. ABS pump relay is relay 17 the black one. But if brakes are stopping you that will be ok.
 
Thanks, I've just been out to it and the pump is definitely coming on, but its coming on every time you press the brake pedal for about 5-10 seconds - is that normal?

I'm having the 'work' they did inspected on Monday before I pay them anything or start leaving reviews.
 
Not normal......there is a black dome on the pump called the accumulator, this stores hydraulic pressure....the pump charges this dome.

The dome should store about 5-6 pedal pushes-worth of pressure before the pump has to run again to recharge the dome.

If it runs every 2-3 pedal pushes, it is tired.....if it runs on each press of the pedal, the accumulator is finished and needs to be replaced....you MUST use the RAVE method of de-pressurising the Accumulator before removal.
 
Hi everyone,

I need some help.

I've just got my P38 back from a "landrover specialist" after over 3 months, long story, but they were changed the wheel bearings and fixed the head gasket, but buggered the electrics and ended removing my LPG system along the way.

Anyway, now its showing ABS Fault & Traction Control faults. The ABS seems to be working (its stops anyway), but I'm not sure how I know if the pump etc is all working correctly. I've seen posts about the pumps and relays, but how do I know if the pump is working and which relay or switch is it?

The brake lights are working fine.

As they changed the bearing is there a good chance its just the sensor? If so how do I check the sensor?

Also, does anyone know what is supposed to be in the compartment next to the battery? The cover is now missing, but as I've never paid much attention before I don't know if there ever was anything in there!

Many thanks


The compartment behind the battery on your 2001 Motronic V8 is supposed to be empty, on the earlier Gems cars it is the location of the ECU. The Motronic/Bosch ECU is behind/next to the EAS Box.

As for your TC and ABS errors, I have been chasing these my self. First job is to check it with diagnostics and see what error codes are there otherwise your fumbling in the dark. As Wammers has said its most likely an ABS sensor that has been disturbed or removed and refitted incorrectly. It does say that the sensor bush (little copper job that pushes into the hole first before the sensor goes through it) should be replaced if a sensor is REMOVED at any time. They are only a few pence so it could be something as simple as that so you could just check that all of the sensors are properly pushed home to where they should be. But best bet is diagnostics and go from there.
 
The compartment behind the battery on your 2001 Motronic V8 is supposed to be empty, on the earlier Gems cars it is the location of the ECU. The Motronic/Bosch ECU is behind/next to the EAS Box.

As for your TC and ABS errors, I have been chasing these my self. First job is to check it with diagnostics and see what error codes are there otherwise your fumbling in the dark. As Wammers has said its most likely an ABS sensor that has been disturbed or removed and refitted incorrectly. It does say that the sensor bush (little copper job that pushes into the hole first before the sensor goes through it) should be replaced if a sensor is REMOVED at any time. They are only a few pence so it could be something as simple as that so you could just check that all of the sensors are properly pushed home to where they should be. But best bet is diagnostics and go from there.
Didn't read title........didmn't see 2001
 
Most ABS sensors are simple coils and they 'detect' very small changes in 'inductance' caused by ferrous metal coming into close proximity to the sensor tip, (the sensor is usually an electrical coil - but could be a more complex proximity sensor).

As well as each wheel having its own ABS Sensor there will also be an ABS 'Ring' affixed to each rotating wheel hub and the ring will either have regular holes drilled around the circumference, (in line with the position of the sensor), or the 'Ring' edge will be 'castelated', (just like teeth cut on a gear - but these 'teeth' will be square and not triangulated).

As the wheel rotates the holes, (or the square teeth), will pass by the sensor inducing a small voltage, (in the form of a rough square wave), that the ABS Computer then uses to analyse what each wheel is doing.

The sensor could be misaligned, open circuit, (break in the cable and/or connector), or it could be damaged, (physical trauma to sensor body due to it touching ABS Ring or due to rough handling), or the sensor ABS Ring could be damaged/misaligned.

The gap between the sensor and the ring is critical, (although I can no longer remember if the 'flux density' is inversely proportional to the square of the gap), but if the sensor is placed more than a few mm from its designated position there will, NOT be enough voltage induced to keep the ABS Computer happy - and will flag a fault.

If the sensor is too close to the ring it will 'detect' the presence of the ABS Ring at all times - thus not differentiating between the 'gaps' so NO square wave is produced and the ABS Computer will flag an error.

There is always ihe possibility that the ABS Computer, (or other associated components), are the cause of the fault but the sensor/ring is the usual culprit in most situations.
 
Most ABS sensors are simple coils and they 'detect' very small changes in 'inductance' caused by ferrous metal coming into close proximity to the sensor tip, (the sensor is usually an electrical coil - but could be a more complex proximity sensor).

As well as each wheel having its own ABS Sensor there will also be an ABS 'Ring' affixed to each rotating wheel hub and the ring will either have regular holes drilled around the circumference, (in line with the position of the sensor), or the 'Ring' edge will be 'castelated', (just like teeth cut on a gear - but these 'teeth' will be square and not triangulated).

As the wheel rotates the holes, (or the square teeth), will pass by the sensor inducing a small voltage, (in the form of a rough square wave), that the ABS Computer then uses to analyse what each wheel is doing.

The sensor could be misaligned, open circuit, (break in the cable and/or connector), or it could be damaged, (physical trauma to sensor body due to it touching ABS Ring or due to rough handling), or the sensor ABS Ring could be damaged/misaligned.

The gap between the sensor and the ring is critical, (although I can no longer remember if the 'flux density' is inversely proportional to the square of the gap), but if the sensor is placed more than a few mm from its designated position there will, NOT be enough voltage induced to keep the ABS Computer happy - and will flag a fault.

If the sensor is too close to the ring it will 'detect' the presence of the ABS Ring at all times - thus not differentiating between the 'gaps' so NO square wave is produced and the ABS Computer will flag an error.

There is always ihe possibility that the ABS Computer, (or other associated components), are the cause of the fault but the sensor/ring is the usual culprit in most situations.

ABS sensors should be pushed in until they contact the reluctor ring. Gap is set when wheel rotates. Sensors on P38 have resistance of around 920 OHMs and have a voltage applied to them by the ECU. The change in resistance as the reluctor ring passes the tip of the sensor creates a pulsed voltage fluctuation readable by the ECU.
 

Similar threads