BAS/ASR light (yet again but different?)

[Allbutt]

Dear Sirs,
Please could you throw some light on my problem? As soon as I switch on the engine of our 300TD Estate (1999 WDB2102252A877169) I get the BAS warning immediately followed by the ABS warning. This then stays on permanently. I have no ABS or cruise control, and the steering lock re-set procedure has no effect.
My very helpful local garage has had their tester on the car which says that the brake-switch on the pedal and the speed sensors are all OK. What else could cause it?

Thanks for you interest,
Edward

 

[colin carnegie]

Edward,

This may be of some use, from an earler thread.


Just thought I would let you know. I noticed the car was a bit sluggish to start, (battery getting low!) so I took the car out for a short drive to have a final check of the ABS system lights, and to recharge the battery. All ABS faults still the same.
Parked the car up, then had to move the car shortly after, battery now fully charged, observed there were no ABS faults, no system malfunctions appeaing on the dash. Took the car out again, all systems good. So the only explination I can think of, for the remaining ABS faults, would be for a low volts/amp's in the battery.

Reading back through some of the other threads related to electrical system malfunctions, the low battery volts/amp's, may well be the cause to retaining my ABS fault, after fitting the drive shaft.

Thanks,
Colin

 

[brandwooddixon]

If you run the car for a period and then turn it off and rrestart the engine does the light go away?

I had a dying battery, which didn't have sufficient voltage on startup to correctly power the self test for these units, especially if left overnight. A change of battery solved the problem.

 

[Allbutt]

Dear Brandwooddixon,

Unfortunately, the light and messages ABS and BAS still come up straightaway even after a good run. It began as an intermittent fault that is now permanent. - I will check the battery and alternator though as I do occasionally get a 'low charge' message.

Thanks for the advice,
Edward

 

[amb67]

Sounds like you may have a failing alternator regulator pack.

Do you own a multimeter?

If yes I can help you check the battery voltage and check the charge rate next time the warning lamps are on.

With the engine off and ignition off to the battery should read anywhere between 10.8 - 12.0 volts.

When you start the engine it should jump to at least 13.1 volts anything less and you have a defective alternator.

Is the alternator drive belt in good condition? Would be my first check.

Let me know how you get on.

 

[Allbutt]

Dear All,

Thank you for all this advice - the consensus seems to be that it is a basic battery/alternator problem. I'll get to it and report back.

Once again, many thanks,
Edward

 

[hmang]

try a brake switch known to be working.

just to be 100%