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U0421 Invalid Data Received Ride height Control Module
Hi.
These error keeps driving me crazy , popping up randomly. First of all, I've found that fuse number 37 (ride height control) was oxidized with a blue/black coat, I have no idea why it looked like this but looked like a drop of water got there somehow. I cleaned everything and all was good for a couple of tens of kilometers and then the error appeared again.
Today for example after I switched to the track mode it immediately appeared (don't know if it is really related to track mode, maybe just a coincidence)
Anyway I have checked the Ride control module connectors (the module behind the fender on driver's side I guess) everything looks fine there, as well as the fuse #37.
Checked the service manual, but unfortunately, there is no troubleshooting information in the SM regarding this error.
U0421 Invalid Data Received From Suspension Control Module
Never had one fail, but this is how'd I'd start:
1. Use a multimeter to resistance test the wiring from there and make sure it's solid. (wiring problem)
2. Try the recalibration in GDS2
If it still messes up, I'd try a new sensor. They look to be about $75.
You need to back up a bit. What problem are you experiencing with the car? It's not unusual for occasional communication errors to occur.
No problems at all, the car runs normally. But as I wrote, sometimes this code appears.
Also I have C0298 08 Parking brake - DTC C0298 08 Park Brake Unlatch Switch Circuit . Performance - Signal Invalid (basically the parking brake is working when I turn it on, but it won't release with the button, only when I start to drive) . But I don't think it's related somehow to the Ride control issue
Sorry, I wasn't clear. I meant that this U dtc code not always appears along with the parking brake code. Sometimes happens that the parking brake doesn't appears at all, and the U code do appear.
Anyone ?
I still have these 2 errors U0421 and C0298 08 Park Brake Unlatch Switch Circuit Performance - Signal Invalid, I guess that the U code is coming with the parking brake code, maybe it's related to the same circuit , anyway, I have tried to replace the parking latch/unlatch switch but the issue didn't go away. Recalibration from the diagnostic tool is working, so from here I guess that the module is ok. Looks like there is some communication issue between the switch and module
I haven't made any resistance tests yet , as I don't exactly understand which pins to check, I need to find someone that knows to read electric diagrams in order to do it correctly
Anyone ?
I still have these 2 errors U0421 and C0298 08 Park Brake Unlatch Switch Circuit Performance - Signal Invalid, I guess that the U code is coming with the parking brake code, maybe it's related to the same circuit , anyway, I have tried to replace the parking latch/unlatch switch but the issue didn't go away. Recalibration from the diagnostic tool is working, so from here I guess that the module is ok. Looks like there is some communication issue between the switch and module
The U0421 code indicates the module isn't configured correctly, however, the FSM says if you have other DTCs correct those first before worrying about the U Code.
The C0298 08 code means there is something wrong with the parking brake and you have noticed something wrong with it.
Once you have that problem resolved see if you still have the U code and only the U code. If the U code is the only remaining code then reprogram the device described by the DTC descriptor, if the U code is still set after reprogramming the device then replace the device and test again. If the code is gone then you are ready to go.
Once you have that problem resolved see if you still have the U code and only the U code. If the U code is the only remaining code then reprogram the device described by the DTC descriptor, if the U code is still set after reprogramming the device then replace the device and test again. If the code is gone then you are ready to go.
Bill
Thanks a lot for the pages from the SM !! For some reason, I don't have these in my SM. This will help me a lot. And yes, you are right 200% , once I solve the parking issue, the U code will go away for sure.
The parking brake worked correctly 2 months ago, everything was fine, then suddenly stopped working and the U-code appeared along with the parking issue
Sorry the flowchart is more like a flow paragraph.
Just clarifying your test.
B,C,D,N,R,S to ground all tested as 1.1ohms or infinite (Greater than 5Ω)?
As I understood from the service manual I had to test the resistance between each other, or I misunderstood something ? If we are talking about resistance tests between each other, so all the tests show "OL" - which is infinite, right ? Except for 2 which I guess is normal (or not ?)
Between B and S 1.1 ohm
Between D and R 1.1 ohm
As I understood from the service manual I had to test the resistance between each other, or I misunderstood something ? If we are talking about resistance tests between each other, so all the tests show "OL" - which is infinite, right ? Except for 2 which I guess is normal (or not ?)
Between B and S 1.1 ohm
Between D and R 1.1 ohm
Should test them each to ground at step 4. 0 will be infinite, which is "greater than 5." Basically infinite resistance in this test would mean they aren't shorted. The manual describes this strangely.
Should test them each to ground at step 4. 0 will be infinite, which is "greater than 5." Basically infinite resistance in this test would mean they aren't shorted. The manual describes this strangely.
Probably missed the step where being said to test them to ground. Will do ground tests and give the results
U0421 Invalid Data Received Ride height Control Module
