Verada KS ABS System

[AQUAR]

Issue is that when the car is unused for a few months (4 or 5 months) the ABS light comes on when I start to use the car again. Eventually with driving and many engine starts it settles and the warning light stays off.

Today I registered to car and of course the ABS light comes on again.
Started the car many times to get the ABS system to stabilise but to no avail.
The pump is buzzing and trying for several cycles on every start.

I wonder if anyone can shed some light as to what might be happening.

Hopefully it will fix itself.

[vlad]

How is the battery? I would take it to a sparky to test it.

[AQUAR]

Battery is fine.
Its not connected whilst the car is unregistered and gets refresher charges to maintain it.

I think it's more to do with the ABS hydraulic circuit being affected somehow after a long period of disuse.
I know its "stabilised" when there is a bit of a sustained ratcheting like noise.
Until then there is just the droning from the pump (and sometimes a short ratcheting noise!) when the controller does its thing on startup.

Purely guessing on my part - the control unit is not happy with the operation of the valves until, after several cycles, everything frees up.

I am curious as to what might really be going on and if others have similar ABS experiences.

Also not sure if this actually generates a fault code in the ECU that needs to be cleared.

This time - about 10 starts in the garage and some driving before I heard the "its all good now".

[ac1176]

ABS controller generates its own error codes which can be read without the aid of the expensive/rare diagnostics unit. A multimeter or LED flasher is sufficient.

Been a while, but I'll see if I can dig out my notes on the ABS unit - I had one that always lit the ABS warning lamp that ended up being due to water damage (don't ask).

[AQUAR]

It would be interesting to see what code the abs controller spits out when its test routine fails, as a result of the car's hibernation period.
Didn't know it had a diagnostics output.

[ac1176]

ABS diagnosis pin is part of the ECU connector under the dashboard next to the fusebox. Can't remember the exact orientation of the connector but I think if you're looking at it head-on, place your DC voltmeter probes on the lower-left most pin and the upper-right pin just to the left of the gap, you can read the error codes by counting the pulses. Long pulses are number of tens, short pulses are number of ones (eg, 2 long pulses followed by 3 short pulses indicates error code 23). Engine needs to be running to get the current codes out:

[ac1176]

The big old workshop manual has a detailed description of each of the error codes and what to do to fault find each one starting at page 35-7-6. Apparently the point at which the ABS warning lamp lights after the keys are moved through the ACC/ON/START positions in the ignition barrel also has hidden meanings.

[AQUAR]

Can you create a PDF of those 3 pages with the error codes?
The ABS light comes on some time after engine start.
IIRC it takes 5 cycles of trying to initialise the ABS system after which it gives up.
I can hear a relay click with the ABS light turning on.
Also the last cycle appears more sustained than the others.

[ac1176]

Sorry, not much time to spare at the moment. Maybe these error codes will get you started:

11 - Wheel speed sensor faulty, front-right
12 - Wheel speed sensor faulty, front-left
13 - Wheel speed sensor faulty, rear-right
14 - Wheel speed sensor faulty, rear-left
15 - Open circuit wheel speed sensor
16 - ABS ECU low voltage supply
21 - Wheel speed sensor input signal missing, front-right
22 - Wheel speed sensor input signal missing, front-left
23 - Wheel speed sensor input signal missing, rear-right
24 - Wheel speed sensor input signal missing, rear-left
25 - Both rear wheel speed sensors faulty
31 - Chipped/jammed ABS wheel rotor
32 - Chipped/jammed ABS wheel rotor
35 - Alternator voltage low
37 - Hydraulic unit faulty
41 - Solenoid valve 1 faulty
42 - Solenoid valve 2 faulty
43 - Solenoid valve 3 faulty
44 - Solenoid valve 4 faulty
45 - Solenoid valve 5 faulty
46 - Solenoid valve 6 faulty
51 - Valve relay faulty
52 - Valve relay power supply missing
53 - Pump drive signal missing
54 - Pump drive signal not switched off
61 - Hydraulic unit faulty
62 - ABS unit inoperable
63 - ABS unit failed

[ac1176]

Some of the codes appear to be duplicates. Not sure what differentiates them. ABS unit may have several codes at available once, so you need to record all of them when the engine is running. From memory the ABS unit will output code 35 if the keys are turned to ACC without starting the engine.