A

aco

New Member

• Apr 28, 2024

• #1

Hello all, I am getting codes C1131-92 and U0421, I've changed valve control block middle and front, fitted a new Hitachi compressor and a tested front replacement airline as the rear suspension is working ok, but the front won't raise. Any help would be appreciated

 

Datatek

Well-Known Member

• Apr 28, 2024

• #2

aco said:

Hello all, I am getting codes C1131-92 and U0421, I've changed valve control block middle and front, fitted a new Hitachi compressor and a tested front replacement airline as the rear suspension is working ok, but the front won't raise. Any help would be appreciated

Click to expand...

What diagnostics are you using?

 

A

aco

New Member

• Apr 28, 2024

• #3

Datatek said:

What diagnostics are you using?

Click to expand...

Hi Datatek, icarsoft V3.0 at the moment I do also have RSW 4can.

 

Last edited: Apr 28, 2024

Datatek

Well-Known Member

• Apr 28, 2024

• #4

aco said:

Hi Datatek, icarsoft V3.0 at the moment I do also have RSW 4can.

Click to expand...

The RSW diagnostics might actually tell you what the codes mean.

 

pwood999

Well-Known Member

Full Member

• Apr 28, 2024

• #5

Based on google search results, most likely it's either leaking air, or the pump is not filling the tank.

The other error "U0421-68 (2F) = Invalid data received from ride level control module"

 

gstuart

D3 Grandad

Full Member

• Apr 28, 2024

• #6

Also worth noting if everything else checks out there are 3 x connectors that are hidden behind the front passenger side wheel arch liner , wires are renowned for breaking or bad connections

Hope that also helps

 

tyregeezer

Well-Known Member

• Apr 28, 2024

• #7

Hi did you change Hitachi like for like or was an amk fitted

 

A

aco

New Member

• Apr 28, 2024

• #8

tyregeezer said:

Hi did you change Hitachi like for like or was an amk fitted

Click to expand...

Hi there, no it was like for like.

 

A

aco

New Member

• Apr 28, 2024

• #9

gstuart said:

Also worth noting if everything else checks out there are 3 x connectors that are hidden behind the front passenger side wheel arch liner , wires are renowned for breaking or bad connections

Hope that also helps

Click to expand...

Hi, the rears went up ok, the fronts initially rose, then after 20 miles went down and refused to rise. I changed the front valve block as I thought that may have been the culprit. I done a soapy water test but cannot see any visible air leaks.

 

A

aco

New Member

• Apr 28, 2024

• #10

Datatek said:

The RSW diagnostics might actually tell you what the codes mean.

Click to expand...

Thanks Datatek, Icarsoft does tell what the codes mean, I'll have to investigate further.

 

Graculus

Well-Known Member

• Apr 28, 2024

• #11

Looks like it's time to get the soap spray out. That DTC is for air supply fault, i.e. a leak. The fact the rear is raising indicates the compressor & lines to the front & rear valve blocks are OK, it maybe a leaking airbag or pipe from the front valve block.

 

A

aco

New Member

• May 17, 2024

• #12

Thank you all for your help, it was a case of looking for what I called a phantom air leak. So I went back to basics and check the voss fittings on the front air springs, the split olive on the off side wasn't sitting on the airline properly, refitted a new olive and the air leak is cured. I am now in the process of fitting new height sensors front and rear. The soap test didn't show up an airleak. I have invested in a GapIID tool now.