Some suspension fault codes this morning
- Thread starter ryanjl
- Start date
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Here's a good thread on the NCLR forum.
http://norcalrovers.org/forum/index.php?/topic/4090-suspension-fault-fun/
According to it, my problem is either the valve block, the compressor itself, or the exhaust vent line.
I'm eliminating the compressor for the time being, seeing as how it was replaced at the dealer about 16 months and less than 20k miles ago.
I can test to see if it's the exhaust vent line by just unplugging it from the compressor and seeing if it works then. If it does, that's what I need.
Or I can rebuild the valve block.
If it's none of those things, it's probably an electrical issue, such as a bad connection or a worn wire. Hope it's not that.
http://norcalrovers.org/forum/index.php?/topic/4090-suspension-fault-fun/
According to it, my problem is either the valve block, the compressor itself, or the exhaust vent line.
I'm eliminating the compressor for the time being, seeing as how it was replaced at the dealer about 16 months and less than 20k miles ago.
I can test to see if it's the exhaust vent line by just unplugging it from the compressor and seeing if it works then. If it does, that's what I need.
Or I can rebuild the valve block.
If it's none of those things, it's probably an electrical issue, such as a bad connection or a worn wire. Hope it's not that.
Speaking as a self-researched expert on the subject as of the last few hours (I say expert very loosely, 'cause I have yet to get my hands dirty with any of it), the issue appears to be that the dryer attached to the compressor contains a dessicant that deteriorates over time, sending tiny particles through the system that can dirty up the lines and valves. That, and rubber parts just get old and don't work as well as they did when new.
scott schmerge
Full Access Member
best maintenance is new drier beads in the compressor, especially if you live someplace that is humid or salty (ie not California or Arizona)
scott schmerge
Full Access Member
exactly. The valves are sensitive to particles pushed through them. You may even be able to just clean your valve without even replacing the o rings. It took me all of 20 minutes to rebuild mine. Simple really
I’d rule out electrical, the compressor, and the exhaust line. If your fault is intermittent, it’s almost definitely your valve block- but I’ve been known to be wrong before...
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Well, the fault started this morning but it has yet to go away since then. When I clear the fault codes, the fault comes back before the GAP tool can even finish.
On my drive home from work, I got the red triangle, "don't go over 30 mph" warning. I checked the faults when I got home, and the U0421-68 returned.
The O-rings are supposed to arrive on Thursday. Hopefully I can get to them that night.
On my drive home from work, I got the red triangle, "don't go over 30 mph" warning. I checked the faults when I got home, and the U0421-68 returned.
The O-rings are supposed to arrive on Thursday. Hopefully I can get to them that night.
scott schmerge
Full Access Member
Sounds good. Let us know what the outcome is!
Hate to belabor this, but it's likely I might be doing this in the dark and the cold, because we (cough, wife) fell in love with a house that doesn't have a garage. I can find the valve block locations for the front and the rear, but there's next to nothing on the center block.
Is the center block inside the plastic compressor guard?
scott schmerge
Full Access Member
Yes! Right next to it... it’s fast to take off. One electrical connection, four hoses (if I remember correctly), and slide it up and off...
You can rebuild in the comfort of your home with favorite beverage while you warm your hands.
Good luck. Let us know if you have troubles...
Sent from my iPhone using Tapatalk
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So, interesting thing.
Got the parts in late Thursday, so didn't have time to mess with it until today.
Put the frame on 4 jackstands before I deflated the EAS using the GAP tool. When I deflated it, the rear actually raised, lifting off of the jackstands. When I removed the valve block right near the compressor, air rushed out when I removed the fitting going towards the air tank, and one other fitting (can't remember which), but the rear is still extended, even with the entire valve block removed and the air lines just sitting there open.
Does this seem wrong?
Could it be my problem is with the rear valve block? How do the individual springs deflate? Do they have their own deflate valve, or does the rear valve block control the inflate/deflate for both rear springs?
Got the parts in late Thursday, so didn't have time to mess with it until today.
Put the frame on 4 jackstands before I deflated the EAS using the GAP tool. When I deflated it, the rear actually raised, lifting off of the jackstands. When I removed the valve block right near the compressor, air rushed out when I removed the fitting going towards the air tank, and one other fitting (can't remember which), but the rear is still extended, even with the entire valve block removed and the air lines just sitting there open.
Does this seem wrong?
Could it be my problem is with the rear valve block? How do the individual springs deflate? Do they have their own deflate valve, or does the rear valve block control the inflate/deflate for both rear springs?
