Hi From The Netherlands & AHC Issues (1 Viewer)

[YvesNL]

how did you manage to remove the ECU? I'm having a hard time...it's pretty tight quarters up there! does unbolting the ecu brackets and leaving the connectors attached give you enough room to test on the back of the connectors? I can't figure out the upper most of the two ecu mounting brackets.....no idea how to get that one unbolted

You're right, if you unbolt the bracket that holds the ECU you will have enough room in the wires to work with.
It is all quite tight but with a bit of patience it should work out. The lower nut is quite easy to get to. The upper nut requires a bit of fiddling around with a ratchet and a 10mm socket.

Have you removed the front (knee) panel?

Wow, there is a lot of rust under the car.
I guess that's what you get when they use salt on the roads in winter.

Did you check that all door sensors are working?
You can't change the AHC in height when one door is open.

Salt on roads speeds up rust very fast.
But the Cruiser was also stationary for two years in high (wet) grass, I think that caused most of the rust.
I will remove most of the rust and coat the underside when the AHC is working again.

I did check all the door sensors, at first one connector had a bad contact and I thought I found the problem of the AHC. After fixing the connection and checking with techstream the door switches are ok and work properly.

 

[NC-Grayson]

yes lower knee panel and as much as I could get out of the way after that have been removed. I can barely even see the top bolt!

 

[YvesNL]

Correct, hard to reach. I lifted the car, got underneath it.
After a few minute it was undone.

Putting the ECU back is even more fun....

I think you'll be able to figure it out.

Good luck.

Update on my truck coming soon.

 

[YvesNL]

Ok. I feel a bit stupid for not seeing this before, but the important thing is that I've located the problem.

Yesterday I got some movement. L to N and N to L is no problem. H doesn't always work but I'll figure that out, I'll probably have to adjust the height sensors or torsion bars.

So How did I find the problem?

I was reading through @NC-Grayson 's threat here.
He also had step values of 0. But after starting the car as @PADDO pointed out they returned to normal.

When I connected techstream and checked the ABS/VSC ECU I saw ECU IG voltage "too low".

SO I thought there must be a missing signal somewhere. So to check I took out the FSM and looked up the terminals of the ECU on page DI218. Connector S9, terminal 2 (second from the right & up) is the "engine idling" signal. When the engine is idling this signal should be 9-14V.

And guess what, is wasn't. It was more like 0.8V with IGN on and engine running.

I used some insulation piercing clips to apply a steady 12V (current limited) to the signal on the ECU.
Closed the doors, leaned through the window, started the car ad pushed "up". The car came up, pushed down and the car came down.
Problem found, now trace the wire and see where the problem comes from.

I immediately wanted to hook up techstream and check pressures and step values, but techstream wouldn't connect to the vehicle. A problem for another day.

Before I found this problem I took the steering column apart and opened up the steering angle sensor. Checked all individual components and forward voltages of diodes and all seemed to be ok. Also I think later models have a different steering angle sensor. My FSM (2005) states it should put out 0 - 5V, but mine has two pulse lines (incremental encoder).

So at the moment I have a higher Cruiser than before, and all the other modifications, repairs and maintenance can happen but that's for another threat. Here's a pic of the Cruiser:

 

[YvesNL]

Ok, so now I need to trace the wire and search for the place where it went wrong.

Below you'll see the schematic of the signal I need:

Right belof the red "0V" that I put there you can see "To Suspension Control". This ts the REG signal, Connector S9 pin 2 on the AHC ecu.
This signal is 0V, if I apply 12v to the signal the AHC works.

Now the signal must come from the Alternator, it is the L signal.
I
My "battery/alternator" warning light is on, If you look at the schematic it should go off when I apply the 12v. But this is not the only light that went off. Here's a picture from before I applied 12V:

And this is after I applied the 12V:

As you can see all lights that should be off are off, no faults anymore. The Airbag light should be on because I took out the drivers airbag. The check engine light should be on because the car isn't started and the seatbelt light is on because the seatbelt isn't used at the moment..

I'll be measuring the signal to the alternator and see if the alternator or a wire/connector is broken.

Also I found this cable tucked away:

As well on the connector as on the fuse panel there is 12V. The wire does not seem to be connected to the signal I'm trying to find/fix. The cable is not long enough to plug it in, it is taped and zip tied to the wire harness. Does anyone know what this wire is?

 

[YvesNL]

Got the alternator out, looks quite used and dirty. Charge voltage wasn't too high while idling 12.9v.

Brought the alternator to a local shop for their alternator test bench.

With the alternator out of the car everything works and there are no warning lights present.

What I do need are some new hood struts, it comes down sometimes:

 

[YvesNL]

Well, it's fixed.

I received the remanufactured alternator and installed it. This is where strange things started to happen.
The AHC worked, but the warning lights stayed on for a bit.

All of the warning lights that were on before now are dim:

I measured the "L" signal connected to the alternator and it was 7,42v so there's a problem.

I started to suspect the Sense line of the alternator, and started to trace and measured it. Everything looked good until I measure right at the connector. While getting my clip off the connector I spotted a damaged wire in the wiring loom to the alternator. +/- 10cm/4in from the connector, just inside the sleeving.

After stripping the wire until I saw clean copper, soldering it and sealing it with some heatshrink the L signal was good and all of the warning lights went off.

So now that everything was working I started playing around with the AHC. Only to find out that it was making constant adjustments and that sometimes I would get two blinks to H or L while N was still lit. Nothing would happen.

At this time I got techstream out and watched the height sensor values. These values were swinging up and down. While FR should be at 0 at the moment I was looking it got to +40 and -30mm. So I replaced this "new" sensor with an old one and the problem went away.

Now the rear is still fluctuating a bit and FL is the only one of my new sensors that is ok. I will replace this one too with the old sensors.

For now, the problems are solved:

 

[portcruiser]

Great work ! Hats off to your dedication and methodic diagnosing process ! Congratulations !

 

[Desert Guy]

I hope this is the most logical spot to post. I've been having AHC issues and am awaiting a new Techstream setup since I hosed the software that was working before, but that's another thing. After reading here I just finished pulling my front sensors, cleaning and checking them. They were clean, so I put them back after checking that there was even resistance across the two outside points. (My meter is analog and messed up. My meter pegs with continuity, so when I see something less I know I have some resistance. Well, after pulling them and giving a check I put them back together and checked the resistance at the end of the cable. One was reading different as it seemed to have a bad connection so I took the cover off again, streatched the springs a little bit and gave the contacts a little nudge to make better contact. The contacts at the end of the cable we both the same at this point. Didn't solve my problem, but at least I eleiminated this as a cause.

So I went to the back and decided to see if the contacts read the same as on the front. No, dammit, but the readings were similar. Here is what I experienced:

The Connector is triangular at the far end and the two horizontal points showed continuity.
One of the horizontal and the lower one showed continuity while the other showed resistance.
This was the same for both, so I figured them to be good, since both going bad in the same way would be strange.
Now the back one. It showed continuity across the horizontal contacts but showed resistance on both of the other combinations instead of just one. I am wondering if this is because ther is only one rear sensor.????

Any comments would be appreciated.

 

[YvesNL]

@Desert Guy

I can't follow you completely, but check the sensors according to FSM:

This is the triangle connector you are talking about.

Measure the voltage and check for a smooth non fluctuating signal.

Have you already got techstream?

If yes, check if your height readings are correct and not fluctiating.
Use a jack to check the entire range.

Check for DTC's, if any note them, clear DTC's and see which come back.

Also, post a screenshot of the AHC data list, non moving, doors closed, engine running, foot off brake, car in park, steering wheel straight ahead, OFF switch not pressed.

If no, get Techstream.

Do you have an FSM? You can use it to check all the signals that the ECU needs and do some more troubleshooting.

 

[KillerBox]

I am glad you found your problem!!! Any pictures of the damaged wire or location of the Sense line of the alternator?

 

[YvesNL]

I'm also glad it works, in one or two days when it has passed inspections I can drive the vehicle legally on the road.

I do not have a picture of the broken sense wire (AKA I can't find it), but is was +/- 10cm/4in from the connector that plugs into the alternator, just inside the sleeving.

 

[PabloCruise]

Wow, what an epic journey! Congratulations on your perseverance!!!

 

[l3n0x]

Awesome job!

My AHC is working(ish), but I do have the “too low” ECU-IG ABS/VSC “issue”. Wonder if I should do something about it as I don’t seem to have any electrical issues. My car has an aftermarket alternator though.

Anyway, did you happen to solve the issue of techstream not able to read the AHC trouble codes - as I’m having the same issue

 

[YvesNL]

I never checked that signal again, everything worked perfectly after the repair.
A few months ago I killed my alternator with mud and water, I replaced it, some things changed.

I cleared the dtc's manually and everything techstream related worked again.
Not sure if these two were related though, there were a few days in between.

 

[l3n0x]

I never checked that signal again, everything worked perfectly after the repair.
A few months ago I killed my alternator with mud and water, I replaced it, some things changed.

I cleared the dtc's manually and everything techstream related worked again.
Not sure if these two were related though, there were a few days in between.

Thanks!

How did you clear the DTC’s manually?

 

[YvesNL]

I believe this was the method:

 

[l3n0x]

I believe this was the method:
View attachment 2006496

Awesome! Thank you very much!