ABS sensor issues after replacing front diff oil seals

[CornwallTreeTom]

Hello folks - title says it all!
I have just replaced front diff oil seals (thanks Tony for the photo instructions) went well, replaced a couple of other seals and swivel hub bearings (lower) as well. Quite an enjoyable job, had some help but it was my first major mechanical experience and no major lash-ups.

The drivers side ABS sensor was a pig to remove it seemed to have swollen in its slot so it needed some serious persuasion to punch and wiggle it out - i reckon i have damaged it in the process as now as the vehicle comes to a halt the brake peddle drops a little and i can hear an electric motor whirring for about 3-4 seconds. I can hear a similar motor whirring as i am engine braking in 1st or second - but that may be something different but i didn't notice it before.

So any tips from anyone would be cool, I haven't priced a replacement part yet, I don't know if its possibleto plug it in to a computer somewhere to re-set the system?

Cheers from sunny england

Tom

[YNOT]

I've never worked on a Patrol with ABS but your local Nissan dealer should be able to code test the ABS for you. I suspect you have damaged the sensor as the symptoms you describe are typical of a faulty wheel speed sensor. The code test should reveal/confirm which sensor is faulty.
If it is a faulty sensor then restting the system/clearing codes won't work due to it being a hard fault.

Tony

[Yendor]

Hi Tom.

Does the ABS warning light come on in the dash?

The ABS system performs a continues self check on it circuits and if it detects a fault it will bring on the ABS warning light in the dash and your brakes will revert back to standard braking system (will lock wheels up under heavy breaking).

I would double check everything is tight, especially caliper bolts, also did you disconnect any brake lines?

[Bigrig]

When you took out the bearings, did you mess with the little cylindrical steel prod (for want of a better word) in behind the lock nuts?? That is the stem for the actuator and if you removed and/or damaged that (or didn't reseat it properly), then that could be the problem also ...

[CornwallTreeTom]

Hi Tom.

Does the ABS warning light come on in the dash?

The ABS system performs a continues self check on it circuits and if it detects a fault it will bring on the ABS warning light in the dash and your brakes will revert back to standard braking system (will lock wheels up under heavy breaking).

I would double check everything is tight, especially caliper bolts, also did you disconnect any brake lines?


Thanks for getting back to me Yendor, Tony & Big rig
Yendor - No ABS warning light, the light works when diff lock is on so I guess it works, the brake peddle drops a little before kicking in with the electric motor noise..... I think its the ABS working when it doesn't need to - if it is would the ABS light come on? I will check on the calipers etc. Cheers buddy

[CornwallTreeTom]

I will check the cylindrical prod ( abs sensor) is done up properly, like i said originally i had to be pretty brutal to get it out and one it was out it looked a bit swollen, i cleaned up the slot for it and put a bit of grease around it so next time it should come out sweet. Thanks for the tips

[CornwallTreeTom]

I've never worked on a Patrol with ABS but your local Nissan dealer should be able to code test the ABS for you. I suspect you have damaged the sensor as the symptoms you describe are typical of a faulty wheel speed sensor. The code test should reveal/confirm which sensor is faulty.
If it is a faulty sensor then restting the system/clearing codes won't work due to it being a hard fault.

Tony


Thanks Tony