- I have a '04 LX 470. I previously had a '99 470 but lost it in Sandy. NEVER had a problem with it's suspension or anything else and it was at 200K miles. The issues with the '04 began a few months ago. I went out one morning and the rearend was all the way up in the air. I took it for a drive and got home and now both the front and back were all the way up. I drove it like that for a few weeks AND got several comments...I took it to a garage for an oil change and he noticed that the reservoir for the AHC was 'low'. He went to Lexus and bought the correct fluid and filled it. Everything was fine for about a month or so. The rearend then started going up and down as it pleased. It would happen while driving and sitting still. I looked at the fluid level and it was well over the 'full' mark. The frontend went to normal while the rear would go from HI to Normal to total Bottom out. I would sit at a stop sign and it would go from HI to normal on it's own or visa versa. I changed the rear sensor. For over a month I was very happy as it seemed like it was fixed. THEN, the front started doing the same thing? This was a couple weeks ago. It sits in the driveway in Normal position. I've driven it only in town as I'm scared to venture far. I am concidering a non-AHC conversion. I don''t want to keep dumping money into a feature I never use. Does anyone know about this as far as ride, cost, etc.? Thank you for any help you could provide. DESPARATE!!!! I need my wheels back! Thanks again, Craig
'04 LX470 AHC Issues! (1 Viewer)
- Thread starter Craig Brooks
- Start date
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From what you have described I'd be looking at one or more height sensors failing to start with. Don't get hung up on the overfilled reservoir tank, as long as it always stayed above min level you shouldn't have air in the system. And if it does bleeding is easy. I hope your mechanic did in fact use AHC fluid to fill. The reason the level was low when your vehicle was stuck in high was the fluid was in the 4 x actuators (aka shocks) - this is normal. I propose a good place to start is to pull DTCs from the system. This can be done easily with no special tools, a couple of inches of wire or a paper clip. Attached is a procedure to short Tc and E1 in the under hood diagnostics socket. If you can pull codes like 11, 12, 13 these will indicate failed height sensors and I'm sure there will be more. Ideally you need techstream with mini vci to diagnose and maintain your AHC, this can be purchased as a package for about $30 and will pay for itself many times over if you want to do your own maintenance. Alternatively find a Lexus dealer that has some experience with AHC systems, many don't and will just throw parts at the vehicle 'till you say stop. Maybe ask the service writer for up to one hour of diagnostics, no part replacement without your authority. One hour might cost $150, if they have any competence they should be able to identify the more significant problem(s). If you have no appetite to repair and maintain your AHC and Adaptive Variable Suspension (AVS) conventional Toyota or aftermarket suspension can be installed. People do it all the time. And when you say you never use it, I guess you mean you don't raise or lower the vehicle via the manual switch. Every time you start and drive it self levels, adjust the damping as per road feedback, tightens up for cornering, anti dives when braking and much more.
uHu
Bridgeburner
As Paddo said. Just adding that failing/flaky height sensors often(normally) don't give codes. But it certainly sounds like either a sensor or cabling. You would most likely be wiser after checking with techstream.
Happened to my 2004, lived in KC at the time they use salt on steroids for salt removal in the winter. It was a corroded sensor. Sounds like you need to replace the sensors.
First try to pull error codes from the system. The codes indicate a more specific causes of the issue. If no code is pulled, as SWUtah said, get your sensors checked.
- Thread starter
- #6
Thanks to all of you who have replied to my issue. Have been away and now need to look into getting this thing fixed. Couple of questions: Would Autozone's tester work OK to pull the codes? Secondly, if the front sensors do need replaced do I then have to adjust them? When I did the rear sensor I did no adjustment and it seems like it's sitting exactly where it should be.
- Thread starter
- #7
Not sure if I replied in the right place. New at this site...Thanks to all of you who have replied to my issue. Have been away and now need to look into getting this thing fixed. Couple of questions: Would Autozone's tester work OK to pull the codes? Secondly, if the front sensors do need replaced do I then have to adjust them? When I did the rear sensor I did no adjustment and it seems like it's sittting exactly where it should be.
uHu
Bridgeburner
Well, if it is the sensors, which is likely, there won't be any codes, most likely; and that's when TechStream comes in, as you can actually see the value of each sensor, and therefore see much more than codes.
Re. adjustment: It's very easy to check the height, if you have the FSM. Those pages are posted here somewhere, in an ahc thread.
- Thread starter
- #9
Hi. I totally rebuilt an antique car from the frame up and yet I have no idea what a Techstream is??? Is that something I need to take it to the dealer or a garage for? Thanks again! Side not: Just noticed that you're from Norway. Had a foreign exchange student from Norway who was a so cool.
uHu
Bridgeburner
Search for TechStream here. Lotsa info.
That's cool, as most of us are just cold...
