200 series AHC problems (1 Viewer)

[lx200inAR]

So this is where I'm getting a bit confused, as currently the RR sensor is showing +27.8mm with the adjuster at the lowest setting, so I can only move the slider up, won't that increase the height setting more rather than bringing it down towards zero?

Sorry..i meant to say RL there, but also, i thought the RL sensor was the one you repaired. Not following along well enough on my phone.

That is correct, I have never adjusted the height sensors, but as stated rears are currently set to the lowest position on the sliders. It's strange though because before the RR sensor link broke, the truck didn't sit level like it does now, it was always raked nose down as you suggested.

I thought you were saying earlier that it always rode more level and without the pitch in the rear.

I've probably been looking at it wrong then. Possibly your RR sensor is reading too high and the truck is trying to lower to get that sensor back to 0 but can't. That would explain why the whole axle is lower on average. Also the swing in after adjust value would mean essentially the same thing, just the opposite way i said it. The ECU can adjust each corner individually, but it also can balance height between the left and right sides with a gate valve. This part is speculation, but I think the ECU uses the gate valve as a safety feature as well when the left and right side read to far apart and allows the pressure to balance. I think the fact that they read so far apart is why the AHC ECU won't allow you to change heights, even though it does try to adjust while you are driving. THis would mean, that you rear end as a whole is probably running about 2" low right now if we assume the RL sensor is mostly accurate and RR sensor needs to be adjusted to reflect the lower height of the RL sensor.

 

[GvsB]

Or you could also replace sensors, since you are saying it took some big hits.

It hasn't had any big hits, I don't use the truck for proper off road driving, just unmade dirt tracks when going to the lake, taking the dog to the beach etc. I think you may be referring to when with the seized ball joint, when the truck tried to lower it imposed enough force to snap the linkage, it may have bent the slider bracket or the sensor bracket?

 

[lx200inAR]

It hasn't had any big hits, I don't use the truck for proper off road driving, just unmade dirt tracks when going to the lake, taking the dog to the beach etc. I think you may be referring to when with the seized ball joint, when the truck tried to lower it imposed enough force to snap the linkage, it may have bent the slider bracket or the sensor bracket?

Sorry, not sure what you mean here. I have no idea how it broke, i'm only speaking to your current state. You said the left and right side are within 15mm of each other by measurement, but probably riding a bit low. The computer thinks the left and right are 3" (73.5mm) apart from each other. So obviously the sensor readings and the ECU are in conflict with reality. Your first goal should be getting the sensors on left and right in the rear to read about the same height if the truck is sitting level.

My initial suggestion was based on thinking you replaced the RL sensor, but since the RR sensor is the one that was damaged, i'd work on getting the RR to move towards the measured height of the RL. I suggest this based only on assuming that the non damaged/replaced sensor is hopefully reading somewhat accurately, so you want to try to get the damaged sensor reading close to it. This theory only applies though if the measured height of the left and right are similar (i.e. within 0-15mm).

Once you get them reading similar to each other, then i believe that will get the ECU and controls working normally. From there you can start worrying about if the overhall height of the rear end is in the right place.

 

[GvsB]

Sorry, not sure what you mean here. I have no idea how it broke, i'm only speaking to your current state. You said the left and right side are within 15mm of each other by measurement, but probably riding a bit low. The computer thinks the left and right are 3" (73.5mm) apart from each other. So obviously the sensor readings and the ECU are in conflict with reality. Your first goal should be getting the sensors on left and right in the rear to read about the same height if the truck is sitting level.

My initial suggestion was based on thinking you replaced the RL sensor, but since the RR sensor is the one that was damaged, i'd work on getting the RR to move towards the measured height of the RL. I suggest this based only on assuming that the non damaged/replaced sensor is hopefully reading somewhat accurately, so you want to try to get the damaged sensor reading close to it. This theory only applies though if the measured height of the left and right are similar (i.e. within 0-15mm).

Sorry I was replying to AnyMal in the above post, not you. He posted I'd said it had taken some big hits!

But your summary is correct, in current "N" setting truck is level and measured heights are very close. Measurements taken on my drive which isn't pool table level, but is pretty flat. Sensor readings in tecstream are 3" different LHS low, RHS high.

 

[AnyMal]

Sorry @GvsB but I assumed thats how the arm boke?

Anyway if its level and hits all height modes im not sure what you are troubleshooting?

 

[GvsB]

Sorry @GvsB but I assumed thats how the arm boke?

Anyway if its level and hits all height modes im not sure what you are troubleshooting?

Not sure if you are seeing all the posts as a lot of my replies are to a user who I think may have blocked you. However a quick summary.

My rear RHS sensor snapped the linkage when lowering , prior to that no problems. Replaced arm and now truck cannot raise to hi or drop to low properly. It gives up.

Techstream shows the rear RHS sensor reading high and the rear LHS reading low, 3" different. Truck is sitting level in "N" setting but before this happened it was higher at the back as per factory settings. I can't drop or raise into "N" using height control as the previous action to raise or lower never completes. So I have to drive where it automatically lowers or raises close to "N".

 

[AnyMal]

Not sure if you are seeing all the posts as a lot of my replies are to a user who I think may have blocked you. However a quick summary.

My rear RHS sensor snapped the linkage when lowering , prior to that no problems. Replaced arm and now truck cannot raise to hi or drop to low properly. It gives up.

Techstream shows the rear RHS sensor reading high and the rear LHS reading low, 3" different. Truck is sitting level in "N" setting but before this happened it was higher at the back as per factory settings. I can't drop or raise into "N" using height control as the previous action to raise or lower never completes. So I have to drive where it automatically lowers or raises close to "N".

LOL yeah man good luck! Be careful dealing with them "experts" though.

If you need actual assistance DM me. Im gonna unwatch the thread. But I know exactly who you are referring to.
They are an expert in nearly every single subject matter! Its kind of incredible actually.
You would think such a person would be running JPL and not playing on a forum.

 

[GvsB]

I finally got the AHC fixed. In the end I had to order another rear sensor from Patsouq as the LHS was also rusted and couldn't undo the adjusting bolt.
When they were finally changed out, both chassis brackets were bent out of shape. Luckily my mechanic, long time cruiser head, he owns a 2011 200, same as mine, used his truck as a comparison to get the chassis brackets back into the ballpark position.
Once he'd installed the new sensors, he doesn't use Techstream but a pro code reader with Bluetooth, which allowed him to fine adjust manually while watching the sensor readouts change until he hit (as close to) zero point while lying under the truck. He said it took a lot of messing around to get right. Now however, it's fully functional again and riding nice and at the right height.

Thanks for all the advice.