Hello everyone,
I seem to have a common theme with a lot of my posts, and that’s that they are mostly related to the ABS system on my Range Rover.
Just to recap - 1999 P38 2.5 DSE
Car has:
New abs pressure sphere
Good used abs pump (I have about 4 to choose from and have swapped them around for testing)
Used but better working abs modulator
Abs ecu that seems to be in good condition as I have a second one that gives wheel sensor faults when it’s plugged in (all wheel sensors are good)
Cut and soldered connectors on the LH footwell, cleaned and reseated connectors on the RH (they weren’t super corroded and I didn’t feel like chopping again)
All ABS related ground points cleaned
Brakes fully bled following proper procedure.
Brakes feel good.
The problem:
Turn on the ignition (doesn’t matter whether engine is running or not, once it’s on ignition II)
All the abs related lights turn on and off accordingly (if you go over the 5mph the abs light turns off) - but anyways there are no faults
Wait around 90 seconds (I have timed this multiple times as I was always getting the fault after driving certain distance from my house, but it has nothing to do with the driving as it will do it just standing still as well)
At the 90 second mark, we get “abs fault”, sometimes traction failure as well but most of the time traction failure only appears once the ignition is turned off.
The only codes I get on Nanocom are as follows:
23-03 Pump relay driver fault : this fault I have literally no idea, I have changed the relay, fuse box looks in good condition, battery is in good condition and I also swapped the abs pump just incase the one I had installed at present was causing the problem.
Intermittently I also get :
01-07 Brake switch failure (fair enough, I changed the brake switch and set pedal position, brake lights all work fine so not sure. Tested the wiring back to the BECM and it seemed to check out just fine.)
Something that’s always bugged me is that even with a replacement modulator, abs pump and a brand new accumulator, my car can only manage two pumps of the brake pedal without running the pump, then it will start the pump on the third press. I know it should be better than this.
Any ideas? I was thinking of soldering the remainder of the wires on the RH side but I don’t really think these are an issue. Other things I was going to try is swapping the pump again but it’s just kind of a messy job and I already did that a few months ago for testing.
Also in my opinion, it a sensor or wiring fault as opposed to a component issue - I feel if it was any of the standard affair (wheel sensor, accumulator etc) we would be getting a normal code, this pump relay code I just can’t find any information on it in order to diagnose or solve my problem.
Something I have noticed is, the pump seems to be way louder than my last one even though it’s visually in much better condition (nowhere near as rusty or corroded). Despite this though, I don’t think it’s causing my issue as the pump does not run when the fault comes up (the car will charge the pump on first startup, then if I don’t use the brakes at all, the error comes up, pump does not run at any stage other than start up so I feel it’s not losing pressure)
Any ideas would be appreciated, I’ve literally never had working abs for the 3 years I’ve owned a P38 and it’s the last job I want to fix before moving forward with the project (reinstating the air suspension etc)
Thanks
I seem to have a common theme with a lot of my posts, and that’s that they are mostly related to the ABS system on my Range Rover.
Just to recap - 1999 P38 2.5 DSE
Car has:
New abs pressure sphere
Good used abs pump (I have about 4 to choose from and have swapped them around for testing)
Used but better working abs modulator
Abs ecu that seems to be in good condition as I have a second one that gives wheel sensor faults when it’s plugged in (all wheel sensors are good)
Cut and soldered connectors on the LH footwell, cleaned and reseated connectors on the RH (they weren’t super corroded and I didn’t feel like chopping again)
All ABS related ground points cleaned
Brakes fully bled following proper procedure.
Brakes feel good.
The problem:
Turn on the ignition (doesn’t matter whether engine is running or not, once it’s on ignition II)
All the abs related lights turn on and off accordingly (if you go over the 5mph the abs light turns off) - but anyways there are no faults
Wait around 90 seconds (I have timed this multiple times as I was always getting the fault after driving certain distance from my house, but it has nothing to do with the driving as it will do it just standing still as well)
At the 90 second mark, we get “abs fault”, sometimes traction failure as well but most of the time traction failure only appears once the ignition is turned off.
The only codes I get on Nanocom are as follows:
23-03 Pump relay driver fault : this fault I have literally no idea, I have changed the relay, fuse box looks in good condition, battery is in good condition and I also swapped the abs pump just incase the one I had installed at present was causing the problem.
Intermittently I also get :
01-07 Brake switch failure (fair enough, I changed the brake switch and set pedal position, brake lights all work fine so not sure. Tested the wiring back to the BECM and it seemed to check out just fine.)
Something that’s always bugged me is that even with a replacement modulator, abs pump and a brand new accumulator, my car can only manage two pumps of the brake pedal without running the pump, then it will start the pump on the third press. I know it should be better than this.
Any ideas? I was thinking of soldering the remainder of the wires on the RH side but I don’t really think these are an issue. Other things I was going to try is swapping the pump again but it’s just kind of a messy job and I already did that a few months ago for testing.
Also in my opinion, it a sensor or wiring fault as opposed to a component issue - I feel if it was any of the standard affair (wheel sensor, accumulator etc) we would be getting a normal code, this pump relay code I just can’t find any information on it in order to diagnose or solve my problem.
Something I have noticed is, the pump seems to be way louder than my last one even though it’s visually in much better condition (nowhere near as rusty or corroded). Despite this though, I don’t think it’s causing my issue as the pump does not run when the fault comes up (the car will charge the pump on first startup, then if I don’t use the brakes at all, the error comes up, pump does not run at any stage other than start up so I feel it’s not losing pressure)
Any ideas would be appreciated, I’ve literally never had working abs for the 3 years I’ve owned a P38 and it’s the last job I want to fix before moving forward with the project (reinstating the air suspension etc)
Thanks
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