Freelander 1 ABS weird issue

Hi guys,

Greetings from South Africa

Not sure if anyone experienced an issue like this:

I bought the car a year ago, and been fixing it up (was a non runner). Working through all the problems and fixing up as needed.
The 3 amigo's are illuminated, and I scanned the car and it said something like "ABS valve stuck" and that the wheel sensors has issues. I just cleared it to get the 'latest' codes and drove a bit.

No issues and no lights came on, then, while driving, the brake pedal just didn't want to depress, I can feel the abs pump (feels like its grinding under the pedal), but no brakes (almost went into the bushes).

I then proceeded to replace all 4 wheel sensors + checked the CV rings (as read on this forum), but the issue persist. As soon as I plug in the ABS relay, there is no brakes, the pedal stays at the top and the pump kicks on.

Will replacing the ABS unit help? Just want to chase down any suggestions you guys have before spending money on another unit.

Kindest regards

Not an expert, but does sound like your modulator/pump is knackered.

If your diagnostics kit does it, you could test the 4 wheel speeds to make sure they look the same as there could be faults in the wiring as well as the sensors and rings - but you'd think it would throw an error rather than trying to jam the brakes on or not.

Hi Grumpy,

Thank you for your reply. Going to check if the diagnostics machine can do live readings, and make sure the wheel sensors are working as it should.

Just a side question to anyone that might know.
Under normal driving situation, when you press the brake pedal, does the ABS pump help you brake in any way? Or is it manual brakes under normal situation?

(Asking cause my audi uses the ABS pump to help you brake, and to hold the car on an incline)

The ABS pump only kicks in when wheels start doing things they shouldn't be - ie locking up or slipping.

If a valve is stuck inside the abs block then try tapping on the block to see if it unsticks. It sounds like the abs is activating unnecessarily and the valve issue is likely why. Although I would check the brake light switch just incase as it will be an input to the abs module.

Tapped the block yesterday, seems bit better for a few minutes. Whats worrying me is why the ABS keeps kicking on. I will check if my diagnostics tool can monitor the wheel speed and see if something is up with that.

haCid said:

Tapped the block yesterday, seems bit better for a few minutes. Whats worrying me is why the ABS keeps kicking on. I will check if my diagnostics tool can monitor the wheel speed and see if something is up with that.

Click to expand...

Look at all of the abs live data as well as the wheel speed sensors. You can usually see what’s active and what isn’t etc. The abs pump should not start and keep running as soon as the abs relay is plugged in

Hi Ross, will do this weekend, just tied up at work during the week. The ABS pump is not running when plugging back the relay, only as soon as I touch the brake pedal, it kicks in, and makes the pedal so stiff you cannot step on it

haCid said:

Hi Ross, will do this weekend, just tied up at work during the week. The ABS pump is not running when plugging back the relay, only as soon as I touch the brake pedal, it kicks in, and makes the pedal so stiff you cannot step on it

Click to expand...

I wonder if maybe it’s a mechanical fault or if that mechanical fault is being driven by electrical input. Try this, remove brake pedal light switch but leave it plugged into the car. Put tape on the switch to keep the plunger in (foot off brake pedal position/brake lights off) and see if it makes a difference. This test can eliminate the brake switch from the problem quickly. At which point the fault code for the stuck valve in the abs pump is likely correct and the abs pump needs replaced.

I’m not sure if the abs pumps on these are coded or not although I suspect not due to the age of these vehicles. Nodge or another knowledgable/experienced person can likely answer that though.

Cheers

The Freelander 1 ABS module isn't coded to the vehicle, so can be replaced with one with an identical part number.

Now a Freelander 2 ABS module is a different story, but thankfully not relevant here.