Same here. I got Techstream going and found codes C1203 and C1851/C1852
"VSC TRAC", "VSC OFF", and "Slip" indicators lights (2 Viewers)
- Thread starter Dharma Dude
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- #22
Hmm. I had no codes when I read it with my OBD2. So you might need more than a ZPC. Did you have a CEL on in addition to the three lights? I still haven't done my ZPC. Too busy the last few days.
No CEL. My reader wouldn't pull it either. But Techstream did.
NMBruce
SILVER Star
Does your speedometer work? Wonder if you broke a speed sensor wire?
Everything works great. Minus DAC and these annoying lights.
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- #26
My speedometer works. Although it reads approx 11% too low because of my larger tires (315/70R17).
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- #27
How do you know your DAC doesn't work? Curious.
Press the button at any speed/gear. Park. Stopped ebrake CDL locked or unlocked. Nothing, no light engages and DAC doesn't keep speed when it's within operating parameters.
The first code is your steering angle sensor. Tends to imply a ZPC will fix the issue. The other two look like residual from air suspension and can be ignored. Steering angle sensor will put up to lights you see and disable DAC, ATRAC, VSC, etc.
I guess this post had bad mojo, I read it and was like damn hope this doesn't happen to me.
Guess what.......
Driving home from towing the military trailer with some lumber, buzzer comes on, lights light up dash vsc, slip, etc.. Everything driving fine still, get about 4 - 5 more stops out of the rig being very cautious, (BTW I live in the country and was on backroads ) waiting for the inevitable, and then it happens. Go to stop 1 mile before the last turn into the drive and brake pedal turns into a brick and won't do crap, threw it into neutral and slammed down on the brakes as hard as I could and slowly pulled the e-brake, got her shut down in time.
Towed it to my uncles shop for them to tell me it was the abs booster pump, he is thinking about $400-$750 total to repair, thinking about doing the whole master cylinder kit and caboodle since I am selling it and can't in good conscience sell it knowing something else may be wrong with it. Will wait to see what my uncle says.
Jeremy
Guess what.......
Driving home from towing the military trailer with some lumber, buzzer comes on, lights light up dash vsc, slip, etc.. Everything driving fine still, get about 4 - 5 more stops out of the rig being very cautious, (BTW I live in the country and was on backroads ) waiting for the inevitable, and then it happens. Go to stop 1 mile before the last turn into the drive and brake pedal turns into a brick and won't do crap, threw it into neutral and slammed down on the brakes as hard as I could and slowly pulled the e-brake, got her shut down in time.
Towed it to my uncles shop for them to tell me it was the abs booster pump, he is thinking about $400-$750 total to repair, thinking about doing the whole master cylinder kit and caboodle since I am selling it and can't in good conscience sell it knowing something else may be wrong with it. Will wait to see what my uncle says.
Jeremy
- Thread starter
- #31
Got my Techstream working on an old XP laptop. I now read c1203 and the "Zero Point Calibration Incomplete" codes.
The ZPC sequence is to do the "reset" and then "test". "Reset" worked fine but then I get an ECM communication error when I tried to do the "test" part of the calibration.
Lights are still on.
- Thread starter
- #32
Update. Took it to the dealer who diagnosed it. Turns out after my lift, the mechanic disable the suspension ECU completely. In fact, he took out the entire height control (H, N, L) and the on/off switch from the console. The suspension ECU has no power. Apparently a Zero Point Calibration requires a working the suspension ECU.
This begs the question of what to do with the suspension ECU after a lift. This forum must have the straightforward answer to this.
This begs the question of what to do with the suspension ECU after a lift. This forum must have the straightforward answer to this.
I didn't remove the suspension ECU, but I did pull the relay and the fuse for the AHC system and removed the switch. No warning lights. Also, none of the height control indications light up in the gauge cluster 
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- #34
I didn't remove the suspension ECU, but I did pull the relay and the fuse for the AHC system and removed the switch. No warning lights. Also, none of the height control indications light up in the gauge cluster
From the wiring diagram. There are three major fuses related to the suspension ECU. The 50A and 10A fuse in the engine compartment. That's for the compressor. those are gone already, along with the compressor. There is a third fuse that connects the ignition switch to the suspension ECU and that 10A fuse is apparently in the fuse panel on the left side, below the dash. I haven't check that yet. I'm guessing I need to keep that fuse but my mechanic might have removed it.
I did pull a fuse in the interior fuse panel. All it did was disable the active suspension and the compressor, essentially killing the whole system.
Tems is the interior fuse label
Yes! that was the one. Thanks Dan!
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- #38
I confirmed the TEMS fuse is missing, which probably means the suspension ECU is completely turned off, which explains why I can't do a ZPC. I'm going to put the TEMS fuse in to see if that will let me do a ZPC.
@DanKunz What's the proper equipment to remove after deleting rear air suspension? Besides the air bags, of course.
My mechanic removed the 20A TEMS fuse, the 50A AIR SUS fuse, the 10A AIRSUS No. 2 fuse. He also remove the entire suspension control switches assembly from the center console. He also remove the compressor and the reservoir but left the height sensors.
Now I have those three lights and can't do a ZPC.
@DanKunz What's the proper equipment to remove after deleting rear air suspension? Besides the air bags, of course.
My mechanic removed the 20A TEMS fuse, the 50A AIR SUS fuse, the 10A AIRSUS No. 2 fuse. He also remove the entire suspension control switches assembly from the center console. He also remove the compressor and the reservoir but left the height sensors.
Now I have those three lights and can't do a ZPC.
Are you trying the pin or tech stream method?
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- #40
Techstream. I assumed pin method would fail the same way because skid control ECU can't talk to the suspension ECU (it's off).
