On and Off ABS Service/Brake assist service - BCM-0070

[aslan]

Hi

Been getting this message on and off for the past couple of months. I thought it was related to a bad CEM / wiring issue but after resolving that it has come back again yesterday.

The consistent DTC I'm getting is BCM 0070. Which points to the ABS pump. I've received advice to get a new unit (module plus pump). I have cleaned the big connector at the brake control module with no luck.

Have anyone else had this problem before? Can the pump only fail? Has anyone replaced or repaired the pump before? I've read the correct pump is difficult to get and is mated to whether the car has DTSC or not and the pump part no is not a good guide.

Thanks!

[aslan]

Forgot to add. Using VIDA I can hear the pump activated. But this is with current cycle status showing no fault so not sure how accurate this test is

[bobdabuilda]

Could be a cracked reluctor ring on front drive-shafts which don't throw up a code... have you checked them?

[aslan]

Originally Posted by bobdabuilda

Could be a cracked reluctor ring on front drive-shafts which don't throw up a code... have you checked them?

Not yet. Any guides around on how to check and replace? Would a cracked ring make a sound? I have this sound from the front right wheel.

[Funky Diver]

I've literally just replied to a thread that has the "process" in Aslan. Mine is suffering the same fate.

Just bought a pair of new rings off the bay for less than £10, so I'll be tackling this after New Year. I would have done a guide, but for some reason on this site the pictures disappear a bit too prematurely to be of any use so I'm not going to bother.

If it's like a clunk, that could be a brake pad moving about in the carrier.

[aslan]

Thanks Funky Driver. Will check the rings first. Today the XC90 is behaving, no error message.

[aslan]

An update, the rings are fine.

The error messages are coming on nearly every day. And almost always after driving for more than an hour. It resets itself in the morning after driving the car for a short distance. Probably the computer self checking and finding the error not present and clearing the codes.

Sounds like a heat issue. I checked the codes again today, the same BCM 0070.



Anything else I should check? Based on the code and what I've searched on the internet, I'm not entirely sure if it's a module or a pump issue. I'm thinking of removing the pump and cleaning the pump connector but can't find anyone solving this problem by doing that.

[aslan]

Solved this issue.

I removed the brake module and the pump. I cleaned the connectors to the pump and the mating surface of pump to hydraulic unit. It didn't look dirty really. I can't find a non-destructive way of opening the pump to inspect the brushes and the clean the insides.

Crossed my fingers and reinstalled everything back. It's been nearly a month now since I cleaned the pump and the ABS error code hasn't come back.

[gmonag]

Result!

[aslan]

I'm updating this thread with some pics as a fellow owner has PM about this issue.





The connector to the pump can be seen above.