Sierrasideways

iTrader: (1)

MOT next Thursday and need this fixed before then.

Story is we put 4X4 callipers on the rear about 2 weeks ago, only did about 20 miles since.

Brake fluid is indeed over the max (haven't got around to trying to fix the issue until this week as I'm off work), handbrake switch appears to work fine as when the light goes off, I exercise the handbrake and light goes on/off as it should.

Sometimes when driving, light is off as normal but then starts flickering out of the blue. Sometimes it's constantly flickering while driving.

I've shorted out both connectors on brake fluid cap(separately for testing purposes) and the problem still stays.

Any ideas please guys? I'd very much appreciate some help as I don't want it failing the MOT on something stupid. Everything else is A1 on the car.

Thanks,

Philip.

Caddyshack

Sounds like a dodgy Earth on the handbrake to me, just check all tolerences

Marc sierra

iTrader: (1)

The ABS computer can also switch on the light, but IIRC it always does this together with the orange ABS light. Perhaps it's a damaged wire somewhere that is shorting to ground (as I believe that is how that circuit works). Does it also do it when the car is standing still? As vibrations can cause movement of a damaged wire.

Sierrasideways

iTrader: (1)

Thanks for the reply. Handbrake switch appears to work when the light stops flickering. It switches on the multimeter too.

Edit: Forgot to say the earth of handbrake is connected to brown/green of handbrake and they're both connected to my Launch Control MSD system, a pin on a switch. Most likely my LC won't work now either as it sees the handbrake up all the time.

Thanks for the reply. Strangely enough it did it only once standing still. I've shorted out the ABS 2 pin plug on brake fluid reservoir and orange ABS light goes out as it should.

I've spent most of the day on the ba$Ł#%d today and now the light is on all the time. Verified handbrake earth is connected to ground and handbrake brown/green is connected to brown/green of brake fluid cap 3 pin. Light flickers with 3 pin disconnected so I'm guessing it's not that. Brown of 3 pin on fluid cap should be connected to ground at front LH fender ( under headlight I'm guessing ) but it wasn't. So no earth on the 3 pin fluid cap but again with 3 pin disconnected it still flickers.

Can't remember what else I did. I'm at my wits end with it to be honest. Breaking seems like a good option just for the reliability factor alone. So sick to death of it. MOT is Thursday. Anything else I can try please before I burn the fucker.

Thanks.

Philip.

Sierrasideways

iTrader: (1)

Possibly a bit OTT with last post

Just looking for some help please...maybe I've made a mistake somewhere or my descriptions are incorrect...if anyone has any recommendations or things to do to help, I'd love to know.

Can't see what else it could be, handbrake switch switches earth and brake fluid cap turns on/off ABS light when I manually move the plunger up and down so doesn't this mean both handbrake and fluid cap sensors are both working???

I'm going to change ABS ECU tomorrow but other than that I'm lost

Any help would be gladly appreciated

Philip.

Sierrasideways

iTrader: (1)

Anyone lads please?

Sierrasideways

iTrader: (1)

Nearly drove me into a mental institution....after loose earth from ECU issue was resolved took it out and hit full boost in 1st to 4th......smiling again

Until next time eh.

Thanks a million for the replies, you were both right, dodgy earths! Took ages to find. Only when going to change the ABS ECU did I move the loom and hey presto the light went out.

Cheers

Philip.

Ade

Mine has a similar problem.... flickers when using the handbrake though. Which also means my launch control doesn't always stay on. Any ideas for that?

Sierrasideways

iTrader: (1)

Try verifying if the handbrake switch is working as it should with a multimeter. It should be (from memory so could be exact OPPOSITE) open circuit when handbrake up and short circuit when handbrake down.

If that's good try shorting out the BROWN/GREEN and BROWN/YELLOW on 3 pin brake fluid cap connector --> Just did this now and it works!

With these 2 pins shorted the handbrake light illuminates and goes off as it should so this bypasses the brake fluid level sensor.

Worth a shot?

Philip.