AHC rear stuck in L, front okay (2 Viewers)

[AtinLango]

I am at it again.

I was so anxious today that I was changing all those bushes under my car. I expected to get the best experience after the change. Note that I was already having a very good experience, and in fact I should not have bothered to change anything - but there I was.

All rubber bushes were replaced. Unfortunately, in the process, the mechanic removed the struts and put them back. That seems to be the beginning of new problems again. The rear is stuck in L, but the front is okay - can move from L-N-H.

The ride is too spongy in the rear, and cannot be driven in that state.

We tried bleeding but there is no pressure in the rear. Any help will be most appreciated as usual.

 

[2001LC]

Check the rear height senor. Possibly the adjusts is loose in the slide.

 

[AtinLango]

Check the rear height senor. Possibly the adjusts is loose in the slide.

Oh, thanks for the prompt reply.

Yes, we checked the rear height sensor - disconnected the switch then reconnected it, but no change.

Techstream also returned error about rear height sensor at first but we cleared it. The error did not return again, but problem persists.

I am thinking that air may be stuck in the system since they removed the struts and put back.

 

[2001LC]

But first, you did not mention if slide arm firmly attached at factory setting. Do make sure.

Make sure sensor arm okay, than since you had an DTC point to rear sensor "Techstream also returned error about rear height sensor". I'd check that. The FSM has a test for sensor, which you'll find by searching this tech forum.

You also did not mention what the pressures reading are or other data in tech stream.

You may be loosing pressure at hydraulic line at top. Check for leaks.

You may have air, but your few bleeds, should have removed. If you still think air in rears. Try lifting (jacking up) rear of vehicle, allowing rear tires to dangle shocks fully extended. Front of vehicle on the ground. Start engine set AHC to high all doors closed. Once in high and pump turns off. Turn off engine. Open both rear bleeders, and lower vehicle back to the ground by lower jacks all the way. This forces maximum fluid/air out of shocks and lines of rear. Close bleeders. Start engine all doors closed. Set AHC to low, then raise to H. Bleed again from high, rear, acc & front. So to not waste AHC fluid, filter through a transmission inline filter, then reuse. Do not let reservoir run to low. Or you'll really have fun re-bleeding many times.

It's also possible, height senor is damaged. They do fail from time to time. I've seen two reason they fail.
1) The ball joint in adjuster arm freeze up, bending and damaging components.
2) The contacts within sensor become corroded. The FSM has a test for this, which you'll find by searching this tech forum.

When the upper control arm was removed. It's very possible, the sensor arm moved or was setup wrong.

 

[AtinLango]

But first, you did not mention if slide arm firmly attached at factory setting. Do make sure.

Make sure sensor arm okay, than since you had an DTC point to rear sensor "Techstream also returned error about rear height sensor". I'd check that. The FSM has a test for sensor, which you'll find by searching this tech forum.

You also did not mention what the pressures reading are or other data in tech stream.

You may be loosing pressure at hydraulic line at top. Check for leaks.

You may have air, but your few bleeds, should have removed. If you still think air in rears. Try lifting (jacking up) rear of vehicle, allowing rear tires to dangle shocks fully extended. Front of vehicle on the ground. Start engine set AHC to high all doors closed. Once in high and pump turns off. Turn off engine. Open both rear bleeders, and lower vehicle back to the ground by lower jacks all the way. This forces maximum fluid/air out of shocks and lines of rear. Close bleeders. Start engine all doors closed. Set AHC to low, then raise to H. Bleed again from high, rear, acc & front. So to not waste AHC fluid, filter through a transmission inline filter, then reuse. Do not let reservoir run to low. Or you'll really have fun re-bleeding many times.

It's also possible, height senor is damaged. They do fail from time to time. I've seen two reason they fail.
1) The ball joint in adjuster arm freeze up, bending and damaging components.
2) The contacts within sensor become corroded. The FSM has a test for this, which you'll find by searching this tech forum.

When the upper control arm was removed. It's very possible, the sensor arm moved or was setup wrong.

Many thanks. I will follow up your guidance tomorrow. Most appreciated!

 

[AtinLango]

All is well.

I removed the rear height adjusting slider and fixed it back. Everything is okay after that.

 

[2001LC]

Took me longer to write up possible. Than you to fix, once onto correct path. Nice going!

 

[AtinLango]

All is well.

I removed the rear height adjusting slider and fixed it back. Everything is okay after that.

Took me longer to write up possible. Than you to fix, once onto correct path. Nice going!

Your insights are very important. Your time is not in vain. I gain a lot from people like you.

By the way, i declined a suggestion by my mechanic to take the car to some "AHC Expert" who i am sure was going to spend the whole day and rip off the system and charge me handsomely.

My mechanic cannot believe that i fixed the problem, yet he had struggled with it in vain for hours the previous day. I am just a car owner. I only observe what mechanics do and also learn from people like you.

Experience is the best teacher.

 

[AtinLango]

But first, you did not mention if slide arm firmly attached at factory setting. Do make sure.

Make sure sensor arm okay, than since you had an DTC point to rear sensor "Techstream also returned error about rear height sensor". I'd check that. The FSM has a test for sensor, which you'll find by searching this tech forum.

You also did not mention what the pressures reading are or other data in tech stream.

You may be loosing pressure at hydraulic line at top. Check for leaks.

You may have air, but your few bleeds, should have removed. If you still think air in rears. Try lifting (jacking up) rear of vehicle, allowing rear tires to dangle shocks fully extended. Front of vehicle on the ground. Start engine set AHC to high all doors closed. Once in high and pump turns off. Turn off engine. Open both rear bleeders, and lower vehicle back to the ground by lower jacks all the way. This forces maximum fluid/air out of shocks and lines of rear. Close bleeders. Start engine all doors closed. Set AHC to low, then raise to H. Bleed again from high, rear, acc & front. So to not waste AHC fluid, filter through a transmission inline filter, then reuse. Do not let reservoir run to low. Or you'll really have fun re-bleeding many times.

It's also possible, height senor is damaged. They do fail from time to time. I've seen two reason they fail.
1) The ball joint in adjuster arm freeze up, bending and damaging components.
2) The contacts within sensor become corroded. The FSM has a test for this, which you'll find by searching this tech forum.

When the upper control arm was removed. It's very possible, the sensor arm moved or was setup wrong.

I have nearly two liters of AHC fluid that I bled in the past two or so months. It was mostly really new and clean. Some had air, which I allowed to settle and all air disappeared. I then properly filtered it again (twice) and kept it closed in AHC metallic can. It looks brand new. Can I reuse this fluid safely?

 

[2001LC]

I have nearly two liters of AHC fluid that I bled in the past two or so months. It was mostly really new and clean. Some had air, which I allowed to settle and all air disappeared. I then properly filtered it again (twice) and kept it closed in AHC metallic can. It looks brand new. Can I reuse this fluid safely?

Sure!