Replace motor in HBB ABS unit

[kiwi1973]

My unit died, loud buzzing sound and breaks failed.
Took the unit out was easy enough, replaced the electric motor and fitted the unit back in, turned on the car and the issue remained.

So now i'm looking to buy the whole assembly because i don't know what else to do other than that.
only thing i can say, is that it's easy enough to pull the unit out and replace the electric motor.

Not sure about the whole mutt thing, i'll let you know once i get the replacement unit if this becomes a requirement.

Edit: just noticed there where 2 pages to your post and you had already done it......

RaRe you don't specifically say in your post, but did you follow the bleeding procedure as set out in either the workshop manual, or also well set out in Youcanlaughs excellent diy post?

Before reinstalling my unit I took just the motor piece (assembled back into its body) and touched its wiring across the battery so that I could see that it was running fine.

That your issue was not resolved could be:

(1) lack of bleeding
(2) something to do with your motor repair - this is easy to establish by getting the motor off and touching its wiring across the battery.
(3) something else - accumulator or master cylinder.

If it turns out to be (2) above then why not just order the motor assembly new (MN102843) as this is about 1/4 the price of the whole unit. (Unless this is what you mean you have already done).

[kiwi1973]

After doing plenty of testing on-road yesterday, including some deliberate hard braking to induce ABS and wheel spin to induce traction control on a gravel road, last night I took the kids and went for what I thought would be a quick jaunt up an off-road track nearby where I'm staying that I haven't done in years. Last time I did it was nearly 4 years ago, doing it downhill, in a trusty old Delica that I use as a runabout (good vehicle actually).

But I was in for a bit of a surprise - the track isn't now what it was 4 years ago. I would have said that back then it was grade 2 with elements of grade 3 - so pretty easy. Now it is solid grade 3 with elements of grade 4. (My ratings may be a bit subjective/inaccurate - but what I mean is not suited to softroaders or non-lifted 4wd). Not what I was intending going on evening with just the kids on board. Also one of those extremely narrow tracks through bush and rocks that you can't turn around on and don't really want to reverse. I decided to continue going up therefore, as long as we didn't come across any truly dodgy obstacles. Though it was a fairly tough track the Pajero just ate it up. I left the front locker off and just left it to the traction control, which had to work a lot, thereby giving this job a really decent test. No problems - all went well. I'm not sure if I can feel a little more feedback/vibration through the pedal, but may just be focused on it more due to just having done this job. I tend to come away from a track like that feeling highly impressed with the Pajero, even though it's nothing new and I've had this car over 6 years.

[RaRe]

RaRe you don't specifically say in your post, but did you follow the bleeding procedure as set out in either the workshop manual, or also well set out in Youcanlaughs excellent diy post?

Before reinstalling my unit I took just the motor piece (assembled back into its body) and touched its wiring across the battery so that I could see that it was running fine.

That your issue was not resolved could be:

(1) lack of bleeding
(2) something to do with your motor repair - this is easy to establish by getting the motor off and touching its wiring across the battery.
(3) something else - accumulator or master cylinder.

If it turns out to be (2) above then why not just order the motor assembly new (MN102843) as this is about 1/4 the price of the whole unit. (Unless this is what you mean you have already done).

Hey mate, yer the motor was all good when i reinstalled, but when i replaced the unit and turned the vehicle on i dont hear the electric motor start and i still have the alarm and check engine light asc light etc illuminated

My intention was to remove the unit again, and check the electric motor, though i suspect it will be fine, and perhaps the pump itself has seized or the electrics on the side of the unit are the issue.

i have found a second hand unit to troubleshoot the issue so we shall see i suppose.

[rykiel575]

Rare try bleeding the brakes first as when i reinstalled mine there was no pressure when i pushed the pedal down.

When i bled the front brakes the solidness of the brake pedal came back 60%

If the alarm is ringing (HBB) alarm it means pressure is low so you have to pressurise it to reset it.

[RaRe]

Thanks for the information, i'll give it another go.
Thing is, I'm not hearing that beautiful electric spool noise at all, indicating the pump is trying pressurize the accumulator.

[kiwi1973]

RaRe - I suspect your ABS relays may have burned out when you had the original fault. You can read through Youçanlaugh's diy post to see how to test and replace these. It could be you just need to replace those relays and then attend to the bleeding process.

I didn't have to contend with any possibility of burned out relays because I was doing my replacement as a purely preventative measure before anything actually faulted.

[RaRe]

RaRe - I suspect your ABS relays may have burned out when you had the original fault. You can read through Youçanlaugh's diy post to see how to test and replace these. It could be you just need to replace those relays and then attend to the bleeding process.

I didn't have to contend with any possibility of burned out relays because I was doing my replacement as a purely preventative measure before anything actually faulted.

Hey bud,
I did consider this before i actually replaced the electric motor, and i checked them at work took the tops off and observed the relay bridge when 12v was applied.
It should be noted that in Youçanlaugh post, he actually has the polarity the wrong way around to activate the relay.
Thanks for the mention though, an easy thing to overlook.

Still might be worth me getting some Tojo ones in the mean time, wont hurt at this point in the game :P