ABS and Break light Fault Codes

[koos smit]

Good morning All,

Hoping someone can help.

Apologies for the long story to follow -
ABS light comes on with the break light and the sound from dashboard. Does not stay on though.

First came on when driving over "bouncy" road going through Birmingham on Saturday. Stayed on for about 20 miles and as I turned into service station it stopped, which makes me think it must be an electrical fault.

After that all good for c. 3 hour drive. Started again on Sunday for about 10 miles and then stopped (after I faffed around with the electrics close to the master break cylinder, but could be coincidence).

On the way back from North Wales to Watford it came on and stayed on for about 4 hours, till I stopped in front of the house, then off again.

I do tow a trailer, but it came on when I was not towing on Sunday...

Straight to garage, with Fault codes (had to use old style reader as the new ones did not pick any faults up):
-C0278: Open or Short Circuit in ABS Solenoid Relay Circuit
-C1241: Low Battery Positive Voltage or Abnormally High Battery Pos...
-C1251: Pump Motor is Locked / Open Circuit in Pump Motor Ground
-C1253: Hydro-Booster Pump Motor Relay
-C1256: Accumulator Low Pressure

Mechanic cleared codes and says to drive and see if it happens again, then might have to get the Master break cylinder rebuilt.

Any advice would be much appreciated.

Have a good day,
Koos

2002 LC100 vx 4.2td. Pre face-lift model.

 

[uHu]

First thoughts:
There is nothing indicating that a brake master cylinder rebuild would help.
When you get several fault conditions like this, the problem is often on a more basic level, like grounding and power supply, or corrosion in plugs or ECUs.
I would check :
- grounding to the affected/involved parts, and to engine, alternator and batteries.
- power supply to the the same, together with relays.
- the alternator plug being loose/corroded can give all kinds of funny faults, like this one.
- Is the battery voltage good and stable.
- plug to abs controller (attached to the brake master), and connection to booster motor (corrosion).

 

[Shayne]

Tow socket is exposed and prone to corrode internally .

 

[koos smit]

Hi Shayne, uHu,
Many thanks for the replies. I will start investigating.
Had a look and the motor itself is very corroded!
First things first though, need to find the alarm under the dash so i can disable it!
Have a good day
Koos

 

[Shayne]

If tow socket turns out to be the problem then disconnecting it kills the alarm , should be a plug behind paneling near brake light on opposite side to the jack cubby usually i think .

Or at least thats the usual location , i never had a 100 series .

 

[SteveJB]

Shayne you really are missing out best put a 100 at the top of your Really Need To Get One Quickly List

 

[Shayne]

The 100 never appealed to me Steve and i can't rightly say why to civilized looking perhaps

That said i didn't really want an 80 i just wanted the mighty 4.2 engine .

 

[SteveJB]

Got to beat it with an ugly stick then wear Rose tinted glasses

 

[Shayne]

If i had one everybody would know it was mine at first glance from a distance .

 

[koos smit]

Update since my last post -
Lights and noise came and went intermittently.
Took a look at the motor and although electric points we're good, the motor was completely rusted.
Bought a £90 ABS motor off ebay and asked garage to fit as a starting point before I have the whole master cylinder re-built.
They did the following:
1. Replaced ABS motor
2. Replaced brake fluid reservoir seals
3. Carried out accumulator blead
4. Carried out full break blead
5. Carried out pressure test

...and when the missus asked what it cost, I asked her what she thought it cost and said, yes that much!

Only done about 100 miles since and no light, so fingers crossed it's done the job. Hoping the chinese motor keeps going, but might just order a spare (planned to keep the old one and fix it, but was in a really bad state).

Have a good one and thanks Shayne and uHu for your input.