e39 ABS and ASC light on

Right, Tried the battery trick and no joy. So I decided to dump the thing on the drive, use the GTI and get xmas out of the way before deciding on the next move.

This morning, however, I had, what is described in the trade, a "right result!". Having pondered over the problem over xmas, I bit the bullet and took it to my usual main agent. I figured they might not be too busy between xmas and the new year. Spoke to the guy i normally try to deal with and explained the story. They were actually run off their feet but he went off to speak to an engineer and agreed to quickly run it in and connect it up to at least diagnose the problem for me. Came back 15 minutes later with the diagnosis. O/S REAR SPEED SENSOR FAULTY. "How much do I owe you?" I asked. "Oh nothing" he replied. Over the moon I walked to the parts department with the reciept for the other rear I'd changed earlier, and they had another one on the shelf. Came home, 10 mins to fit it and BINGO, ALL WARNING LIGHTS OUT AND CRUISE BACK TO NORMAL.

To say i'm pleased is an understatement. This dealer consistantly gives me excellent service and an e mail will be off to Bracknell once again, to recommend them for the dealer of the year again.

Thanks for all your help. Just the Thermostat to replace now (it's the common failing, Stuck open).

Happy new year to all.

Trevor

now thats a good idea. I'll give it a go. It's strange that before I changed the wheel sensor the cruise worked (abs and asc was down). Now I've changed the sensor the cruise has pack in also. i'm almost believing that maybe the new sensor is faulty.

Thanks again

Miles

In life you can only truly speak from personal experience and it appears to me that there are many other e39 owners experiencine the same as I. Only yesterday I was at an Xmas do and one of the guys there has been brought up with / cut his teeth on BMW's. His father is a respected specialist who is ex BMW main agent gone it alone but is now starting wind it down and take it easy. His specialist subject, as is his son's, is the e30 (which is handy for mine) and the e28's. We were having this very conversation yesterday and although they say that the e39 is a great car, they agree that the e39 can be a prone to numerous gremlins that the e34 never had. In addition to this they are so complex and "sewn up" so to speak that curing many of the faults can be a nightmare.

I suppose this could be put down to the fact that they 1. have more toy's as standard and 2. are more technically advanced. However I still find it all very fustrating. I have a lovely car that I truly love but the thought of driving it tomorrow with the dash alight with a yellow glow does nothing to light my fire and depresses me to say the least.

Regards

Trevor

Thanks bigpow. Everything points to wheel sensors. However being pulse generators, trying to measure resistance is sketchy. Now waiting for an osciloscope to become available so that i can measure / compare the sine wave generated by each wheel sensor.

I'm going to throw the cat amonst the pigeons now. Anyone notice how many posts there are on this forum regarding e39's and silly niggly problems compared with the e34? I have and it appears to me that (and I'll re assess my thoughts once my car is "better"!) the e39 is not as reliable OR has the same quality as the e34's had. At the moment I would have to seriously re consider that 530 sport I was going for next.

Thanks again guys for all your suggestions. If anyone has any more ideas as to curing my problems I'd love to hear them.

Cheers

Trevor

Going by the tech data i have for the 2000yr e39 523, codes are only accessible with scan tool.

My data does not list abs codes for this model, but if connected to a scanner, the codes and meaning would be displayed.

If you have an independant local to you with a Snap on scanner, they will be able to check the abs for you

My snap on scanner has this function, and also allows live abs data when driving, therefore you can check speed signal from all 4 wheels at same time.

If you need any more info, give me a shout.

Gordon

Check that your brake lights are working.

Not sure if they are linked on bmw, but other manufacturers make there vehicles to disable cruise control if brake lights develop a fault as pressing brakes cancells cruise and could be dodgy if brake lights have failed.

Regards,

Gordon

Okay, I've changed the sensor on the n/s/r. Vines had one in stock. However the lights are still lit. I reckon I'm stumped now!

I've got to go over to Homebase now to get some new bulbs for the christmas tree lights. How ironic is that? The lights on the tree don't work and yet I've got more lights up on the dash of the 5 than Regents Street? Maybe we'll hold christmas in the 5 series this year!!!!!!!!!!!!!!!!

Cheers 

Trevor

I would say you have found your fault.

It could have been held together just enough for it to work and the final straw was inevitable and it finally went.

It's broken anyway so you should really fix it if it is the cause of the fault or not.

Why is it always the last screw/bolt/nut that you come too is the problem? 

Andrew

Right, Not such a successfaul day as I would of hoped. We tried to measure the resistance on the disconnected speed sensors and could not get any reading from any of them. So we tried taking them out and cleaning them. All was well until we got to the nearside rear. The bolts on all of the others were perfect and once loosened could be undone with my fingers. The nearside rear was VERY tight right the way out, I kept winding it back in and out until I got it out............and out fell half the mounting of the sensor. It has obviously been broken for some time as there is a fair bit of dirt ingress on the broken surfaces.

So, I've put it back for now held in place with a penney washer until I can order one tomorrow..............and you've guesed I still have both lights lit.

Do you reckon I've found the fault or is it just coincidence? it seems strange that the system has been perfect up til now, even with a broken sensor. I feel another big bill coming up!!!

The e39 (as per the e34 before) has a seperate oil cooler for the auto transmission, sandwiched between the cooling system rad and the AC condenser rad. Not sure what happened to the one on my e39 but i just came out one night to a pool of transmission oil under the car. Wasn't sure at first as the new style fluid is not red but clear almost like apple juice. Being a G/box with no dipstick your never sure how much oil is in there and it looked like a cow of a job to replace the cooler so I left it to Vines (Redhill) to deal with. They were really good and dropped some of the labour as I'd already diagnosed the fault and partially stripped the car (belly pan / front lip spoiler off). I had to do the one on my last 5, an e34, as well! That had been stressed by the "specialist" I bought the car from when he changed the AC condenser without removing the rad and moving the cooler out of the way (the rad shortly sprang a leak as well). They just pulled the rad and cooler back enough to slot the condenser in, fracturing both in the process!!!!

I'll report my finding on the wheel sensors. Game plan is to get it up on stands, have all four wheels off, measure the resistance on all four sensors and go from there really. Fingers crossed eh?

Thanks again

Trevor