19 Braking system

[|sAs|]

Hi.

My cabrio has a problem with the Bendix ABS system. The long term plan is to ditch it but I don't have time before inspection (MOT equiv.)
The pump works and builds pressure but the light stays on. I think the targets and sensors are ok because it worked from time to time last year. I think it's an electrical problem close to the ABS unit due to having been sprayed with coolant from a leak by the hose connection to the heater core. I have a LHD car so the braking is just by the expansion bottle on the right side looking from the front.
There is braking fluid to the MAX-mark in the bottle.
I'm fairly experienced with a multimeter so I have no problem measuring, but I don't know what to measure and where..
Anyone have a workshop manual for the 19 Bendix ABS system?

Second question; what do I need to convert to a servo-assisted system? I'm guessing the servo and brake master/fluid bottle. Pedal assembly?
Do I need to replace all pipes?

 

[DaveL485]

Does the yellow abs light come on and stay on all the time? Does the red handbrake light stay on after you release the handbrake? Be more specific about the warning lights and what they do and when.

 

[|sAs|]

The yellow ABS light came on and sometimes flickered a bit before staying on. The red light always went off.
I replaced both the engine to chassis and the gearbox to chassis earths during the weekend and after that both lights have gone out every time. The GB -> chassis didn't look very good, especially on the chassis side of it, it looked like it had very poor connection.

 

[|sAs|]

Aaand it stopped working again.
I need to get the 19 through a re-test, it failed last month due to ABS warning light, an exhaust leak and leftover oil from when it decided that the radiator was a better place for oil than in the engine).
I've fixed the exhaust leak and cleaned the underside of the engine.

Does the yellow abs light come on and stay on all the time? Does the red handbrake light stay on after you release the handbrake? Be more specific about the warning lights and what they do and when.

When I turn on the ignition (without handbrake) the red warning light doesn't come on, the yellow comes on. The yellow goes out while cranking and flickers once when the engine is running and then stays on. While it was working I heard maybe 4 clicking noises coming from the ABS unit, I assume that is from the self-test, both when turning on the ignition and then again when the engine is running. Now I don't hear any clicking.
Is there some way to force a self test?
Last time it came on I left the car with the battery disconnected over night and then it worked for a couple of days after that.
The red light never comes on except if I pull the ABS fuse.. (Tried to trigger a self-test, didn't work.)

 

[DaveL485]

Test the wheel sensors for resistance. Though it shoulds more like a master control unit problem unfortunately!

 

[|sAs|]

Do you know what the values should be?
I also think it sounds like a control unit problem, is there anything that can be done?

 

[|sAs|]

What is necessary to replace it with a standard servo-assisted system?
Servo and master cylinder of course but what else?

 

[DaveL485]

Do you know what the values should be?
I also think it sounds like a control unit problem, is there anything that can be done?

Well test all 4 and if one has significantly different resistance you know its a problem. IIRC the 21 Turbo ones read around 1.14ohms or something like that.

 

[Big Steve - Raider]

@Nick Kettle had a bit of a play with ABS systems with the kit he put on his 5GTT. Perhaps he can help?

 

[|sAs|]

I may be able to borrow an XR-25 for a week.. Hopefully I can make out where the problem is then.
Plan B is to put it away for the rest of the summer (most likely) and take a week's vacation and borrow my fathers workshop (with a lift) and replace the entire braking system, bar the rear discs/calipers.
Probably a Laguna servo, master cylinder and bottle. R19 16v pedals for non-ABS, new brake lines, Pug 406 Brembo with Clio 172 high carbon discs. I'm hoping it's not an engine out job on left hand drive 19's.

 

[Nick Kettle]

From memory the controller is in the abs modulator, its got an 12v ignition feed, perm 40A 12v feed from the battery, 4 x 1000 ohms abs sensors and the abs light on dash, that's it. Mine does a test when you first move off, you hear it kick in for a sec and that's it.

Hand brake position has no effect on it
Low fluid has no effect on it

 

[|sAs|]

I haven't been on here for a while but I did manage to get my hands on an XR-25 for a while. As soon as I plugged it in, the car did the selftest and the light went out. It has been working as it should since then.
I still have the XR-25 for a few weeks more. Hopefully I can get some info out of it.
Anyone has experience using it? I could use some guidance

 

[DaveL485]

Anyone has experience using it? I could use some guidance

@Chet T16 and @Red21 are the resident XR25 sexperts.