Winnebago ABS fault

[T1 Terry]

Unplug the ABS module, every wheel sensor, the pressure sensor on the brake pressure booster unit and the battery. Turn the ignition on while the battery is disconnected, pump the brake pedal until it goes hard. Turn the ignition off, spray contact cleaner into every sensor plug, check none of the teeth or chopper plates are damaged or have mud in them, then plug every connector back in after a squirt with contact cleaner. Connect the battery and turn on the ignition, can you hear the brake accumulator pressure pump running and then stop? Wait a few mins, does it start up and run for a short while then stop? If so, you have a leaking pump, check valve or seal ... or air in the ABS ....
If it all works as it should but the light remains on, look for a rebuilt unit out of the USA.
The Toyota Prius is renowned for accumulator failures but there is quite a market for rebuilding them in the USA making the replacement unit a heap less painful to the wallet and comes with a complete replacement guide and return packaging to send the old unit back ..... hard to beat really, so if the problem is a know fault there is every chance the same service is available.

T1 Terry

[supersparky]

I have separated and contact cleaned all the connections and checked all individual resistance of sensors all the way back to the EHCU which is down near the diff in this. Everything measures as expected by the procedures in manual. The voltage to the module is good. But I still get fault code 14, which is a low voltage fault or a failed electronic control module that controls the pump. It will not reset using the procedure in the manual. A sticker will have to do for a while, until can do a bit more research.

[T1 Terry]

I have separated and contact cleaned all the connections and checked all individual resistance of sensors all the way back to the EHCU which is down near the diff in this. Everything measures as expected by the procedures in manual. The voltage to the module is good. But I still get fault code 14, which is a low voltage fault or a failed electronic control module that controls the pump. It will not reset using the procedure in the manual. A sticker will have to do for a while, until can do a bit more research.

Give it jump start with 24v or 48v, then it really will need replacing Can you determine the electrical load on the supply circuit so you can duplicate the electrical load and test the voltage?

T1 Terry

[supersparky]

Havent tried that yet. Will give it a go over the weekend. Or rmaybe Monday. I'm tipping it will be open circuit and that would give s low voltage reading and /or a module fail.

[Peter]

We had the ABS light come on in our Explorer motorhome on a Toyota Hilux whilst on Gibb River Rd last year turned out that we had to replace the cradle in my terms the wiring loom in relation to the Abs due to a short circuit. Toyota had to order it in total cost about $250-00. Took a couple of hours labour.

[Peter]

We had the ABS light come on in our Explorer motorhome on a Toyota Hilux whilst on Gibb River Rd last year turned out that we had to replace the cradle in my terms the wiring loom in relation to the Abs due to a short circuit. Toyota had to order it in total cost about $250-00. Took a couple of hours labour.

[T1 Terry]

Havent tried that yet. Will give it a go over the weekend. Or rmaybe Monday. I'm tipping it will be open circuit and that would give s low voltage reading and /or a module fail.

The most common problem with all ECU related crap is the negative (earth) link to the body getting crap all over it and stuffing up the clean contact. Some haven't even cleaned the paint off to make a good contact and none of them put any contact paste like Alminox between the faces to stop corrosion.

T1 Terry

[supersparky]

Today I checked checked all the supply voltages, changed the fuse, measured all resistances again. Also checked earth connection resistance 0.1 ohm. Contact cleaned all contacts and reassembled. The motor circuit is over 1.0 meg ohm from + to - which I can only assume is bad. The motor still fails to run when the ignition is turned on. Did all the diagnostics from the Isuzu ABS webs pages. Fault still won't reset. The smiley face sticker is looking better every day , because if I pull the fuse out the hill start assist doesn't appear to function correctly.