E2 Error when airing up rear shock

[kbert777]

OK, I looked through the archives and couldn't find anything specific to the E2 error on the CLASS system. Here is the scenario, bike is a '89 with about 75k miles and tons of service records since new:

 

When airing up the rear shock using the automatic setting of the CLASS, the pressure never gets above 35 psi for the rear shock. At about this range the pressure stops rising and the controller goes to E2 and cycles after 5 seconds to reset. E2 error code indicates that the controller does not detect a rise in pressure with the compressor running.

The compressor runs and sounds relatively healthy, I really don't have a reference to compare.

 

Here is what I have done so far:

1. Re-soldered the CLASS controller, didn't find any broken solder joints, but re-soldered anyway
   
2. Serviced the desiccant, found it to be pink in color, heated in the microwave until dark blue, checked the filters and replaced the O-rings in the container and lines
   
3. Found the air intake filter almost disintegrated, disconnected the airlines and forced the compressor to run, replaced all the O-rings, cut a new air intake filter and re-installed
   
4. Checked the valve block and pressure sensor, disconnected the air hoses and cleared the passages with the compressor
   
5. Check all electrical connection, disconnected, cleaned and greased connection, checked for battery voltage at compressor
   
6. Checked for pinched air hoses to the rear shock, disconnected hoses and manually inflated shock.
   

The funny thing is that I can manually block the air fitting for the rear shock at the valve block and the pressure will rise up to 71 psi without any problems. I tried airing the rear shock up using the manual feature and if I let the compressor just run for a few seconds the pressure will ultimately begin rising. I can even get the rear shock up to 85 psi this way. But with the automatic function the pressure will not go past 35 psi with timing out into E2.

 

Has anybody encountered this before? I know the air suspension on these bikes is touchy, but it drives me nuts. Two-up I really like running 71-75 psi in the rear, running this solo almost breaks my already damaged back.

Has anybody a know good compressor and valve block laying around to verify that the problem is in this area?

 

Thanks in advance for all your comments,

 

Klaus

[mraf]

Does sound like a tough fix. Any time mine was acting up it was always the solder joints. If I had to guess it sounds as if your compressor is working fine. The problem sounds more attuned to the Class controller itself.

[Sheradan]

Mine had a bad circuit board and I kept getting E2. Hate to state the obvious, but the bike is on the center stand when using controller?

[kbert777]

Thanks for the comments, this still has me stumped.

 

I initially suspected the controller too, even after re-soldering it might still have a bug. A while back I purchased another controller of EBay, which ended up having a whole bunch of unrelated problems, mainly some severe corrosion and delamination of the circuit board. I was able to get the controller up and running for a few minutes, even if the display is flaky and it took a few tries to get through the self test cycle. In the end the result is the same, the front will air up without any delay, the rear stalls at around 35 psi and the controller will display E2.

 

This lets me to believe that the problem has to be the compressor or the valve block/ pressure sensor. I ended up ordering a used compressor assembly from Pinwall Cycles, supposedly of a 7k mile bike. I am also going to replace the compressor relay, while it measures fine for resistance with or without load.

 

Sheradan brings up another great point too, the CLASS system is definitely designed to be operated with the bike on the center stand. It is not very obvious in the owner's manual, but the service manual emphasizes that the automatic set values are given for the bike on the center stand.

 

If anybody has a know good or usable controller laying around, I would be interested in borrowing it for testing or buying it outright for a spare.

 

More updates to come, please keep the comment coming...

 

Klaus

[kbert777]

Ok, I think it's under control. Turns out the actual compressor was weak or worn.

I ordered a used, complete unit from Pinwall and just replaced the compressor, pressure to the rear shock now rises without any problems and hesitation.

 

This was driving me nuts, hope the fix lasts for a while...

 

Klaus

[Marcarl]

Ok, I think it's under control. Turns out the actual compressor was weak or worn.

I ordered a used, complete unit from Pinwall and just replaced the compressor, pressure to the rear shock now rises without any problems and hesitation.

 

This was driving me nuts, hope the fix lasts for a while...

 

Klaus

Keep your desiccant dry, and you should not have any more problems. Dry it every two years.