e39 - DSC light on

[DavyC2]

Long story short - I suspect a stone got stuck between the front disc and the guard on my wife's e39 (it was making a very loud noise, when she was driving, I arrived and drove it back and forward a few times and then it stopped) when I was bringing it home the DSC, yellow handbrake (DBC ?) and ABS light came on. I took off the disc and caliper but couldn't find any visible damage apart from a few scrapes), took out the ABS sensor and cleaned it too.

Plugged in my diagnostics which i only got on Thursday (cheers Gar) 3 faults came up

1. 97 - Steeing angle adjustment necessary
2. 88 - Precharge pump
3. 92 Pressure sensor (plausibilty precharge pump)

I cleared them and the 2nd one keeps coming up.

88 precharge pump.jpg

The DSC light is on all the time, The ABS one is going on and off when it feels like it (not always on at start up) and the DBC one has come on and went again twice.

I checked all the fuses and they seem fine, I did a quick wheel speed sensor test (just driving up and down the yard with the laptop on my knee ) and they all seem to be working too.

How do I check the precharge pump ? Can I put 12v onto it ? Or is it more than likely a problem with the ABS module ?

Any help appreciated.

[Gar]

Have a look through the history of the car davy see if its ever had the abs module refurbished at any stage in its life ,also look under the bonnet at it and see if theres warranty stickers (like void if seal broken) if there its been done if not I doubt its been done its a very common problem and throws up heaps of errors its caused by the heat from the engine as the heat shield doesn't protect it

Check the part no. The one that mostly fails ends In the digits 001 you can buy 2nd hand but its best to refurbish the unit

Im not postitive this is your problem but have a feeling this is whats causing it

[DavyC2]

Have a look through the history of the car davy see if its ever had the abs module refurbished at any stage in its life ,also look under the bonnet at it and see if theres warranty stickers (like void if seal broken) if there its been done if not I doubt its been done its a very common problem and throws up heaps of errors its caused by the heat from the engine as the heat shield doesn't protect it

Check the part no. The one that mostly fails ends In the digits 001 you can buy 2nd hand but its best to refurbish the unit

Im not postitive this is your problem but have a feeling this is whats causing it

Thanks Gar, had a look around it, just checking for loose connections and stuff and doesn't look like it was ever changed, don't see anything about it in the history either. Strange the way it came on same time the stone got stuck, maybe the ABS/DSC light coming on just triggered the fault in the module ? If it was the module would the ABS light not ne on the whole time then ? I'm guessing there is the no real sure rules with these type of issues/errors ?

[Gar]

To be honest I really dont know enough about as iv never experienced it myself and dont want to guide you down the wrong route so il bow out for now and let some with more knowledge on it post

[Gar]

Anyone any input for this man ?

[DavyC2]

How do I check the precharge pump ? Can I put 12v onto it ? Or is it more than likely a problem with the ABS module ?

O.K. I tried the "Activate" function on the diagnostics for the precharge pump and nothing happened - well I think that's what I did anyway, still trying to get the hang of it

I applied 12v to the precharge pump and it ran so I leaning more to the module even though it's a 002 prt no.

Anyone else before I go and get a module ? Think I'll try and get a second hand one as I'm still not sure it's the problem.

[Gar]

The good news is 001 modules are the most expensive they can fetch +200 as there in high demand the 002 are generally a good bit cheaper

[DaveG]

If you want to drop down to me sometime I can fit a module for you and see if it sorts it.then you'll know. Very hard to diagnose as there can be any no of faults showing up.

[DoktorB]

Precharge pump is a common failure.

I would replace it before the control moduel as its cheaper and especially when you are getting the code for the pump.

[DavyC2]

If you want to drop down to me sometime I can fit a module for you and see if it sorts it.then you'll know. Very hard to diagnose as there can be any no of faults showing up.

Cheers Dave, very generous offer, I'll let you know how I get on.

Precharge pump is a common failure.

I would replace it before the control moduel as its cheaper and especially when you are getting the code for the pump.

That's what I was thinking at first but it ran when I put 12v onto it :huh: