[joel]

Hello there (this is my first post since joining over a year ago), I wonder if you could relay what signs caused you to suspect the OTR relay(s) had failed. I’m trying to trace the cause of an issue I’m dealing with (both Low and High A/C Press lights and Compressor orange light (on the Dash) constantly cycles on and off) and wonder if you faced similar symptoms ?

Appreciate the feedback, if possible.

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1999 XLV X-6872,  liberty #440

[Michel]

Michael: GOOD LUCK. I had same problem and it appears our coaches are of similar vintage. At the time my warning lights did this, the compressor was engaged and operating but the condenser fan was not. It only occurred once or twice and Prevost Mira LOma and I have been unable to track down as system is now functioning. Is your OTR working now or is this a semi-permanent malfunction?

[Bill]

Michael,

Electrical failures of that nature usually don’t provide clues regarding where to look so the best course of action when there is a failure is to use a multi-tester and check for voltage or continuity.

Prevost has excellent wiring diagrams on their web site that can be used to assist.

[Archived]

Thank you both for the quick response. My issue is semi-permanent, in that it cycles on for 10 to 15 seconds (and cools), then it goes off (clutch disengages) for about the same amount of time. I was trying to see if these were tell-tale signs of something obvious but I’ll take my Voltmeter and start checking/hunting around. If I find anything relevent, I’ll post it back for general knowledge.

Much appreciated.

[needtocamp]

HI, Sorry I screwed up your name. Is the condenser fan (right side of bus) running?

[Archived]

I think Joel is on the right track. When the condensing fan is inop the system has high pressure that should trigger a light on the dash that indicates that.

But in the absence of a light, turn on the system, set it to the coldest position, and open the condenser door. The fans should be running. If not that explains the short cycling.

[Archived]

Michael, initially when my relay failed it failed closed, and the evaporator and/or condenser fan would not turn off, even with the igition key off. There were not any dash warning lights.

When I got to where I was going, the relay failed open, the fans would not come on, and the compressor light on the dash would come on.

If the fans are working, you may not have an electrical problem at all, it could be something as simple as its low on freon and the protection switches are protecting the system as designed. Get pressure and temp gauges on it and see what its telling ya.

[glen]

Joel/Jon, thank you for the additional info/pictures/lines of investigation. As far as I know, my fans are running properly (I still kick up a massive dust storm when I pull into a dusty area and forget to turn it off :-)) and I have checked the contacts (for good measure) and they are fine.

I was thinking electrical but perhaps as Joel points out, the issue is as simple as low on Freon (which, now that I think of it, was the case a year ago when I stopped at Liberty in Stuart – 7lbs low). Cue in the lighting of a light bulb ! I’ll look into this aspect as it now seems a more probable cause. A small leak in a 16 year old system may not be that improbable !

I think I’ll watch the OTR Webinar on the Prevost maintenance site, it may help me orient my gyros.

Thanks again to both of you.

[Fred F.]

On my old coach it was low freon a year or so back that caused the light flickering.

[Archived]

I would agree that it’s most likely low freon. But there is a ground wire from the compressor clutch that could be verified also.

[Chuck & Katrina]

How do I get to the Prevost Maintenance site?

Thanks “95 XL40 w/OTR

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2000 Featherlite H3-45

2024 Jeep Grand Cherokee

Leesburg, FL

[Tim]

Here’s the MX Manual for your bus: 1990-2000 MX Manual

Here’s how to get there: PrevostCar Parts & Services website

[Mark]

Well seems i have a issue with our OTR . She stopped working the other day in 112 temp so needles to say I need to focus on the repair . So after some reading and research here I found the circuit breaker tripped . Thinking I dogged a bullet i reset it and turned the air back on after warming the coach up a bit . So while I’m sitting there a few moments and nothing is happening except seeing the fluid in the glass moving around I hear a bang and smoke is exhausting loud and fast . Well after shutting it down and taking a closer look it appears the pressure split the hose to the left going over the fuel tank . O so much for a easy fix . Not sure what caused it but have an appointment Tues at a Prevost recommended shop here in St George . When repaired i will report back and update .

[Chuck & Katrina]

Good luck on the Prevost shop and keep us posted. Went to start mine a couple days ago and the pop off jetted the freon on the accumulater tank. Condenser fans didn’t come on and have to find out why. Always something it seems. Anybody wanna buy a cheap 1991 XL as I’m getting tired of the hunt. Wish Harry, “The Go To Man” was closer to fix my little problems. Well at least he sends me greenbacks to keep mine rolling.

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2000 Featherlite H3-45

2024 Jeep Grand Cherokee

Leesburg, FL

[Jim]

Looks to be a Relay , so they are looking for one . As Don said we should cary a few . If i had one i would be on the road within a hour . My bad I guess . I will order a few . Thank you for the link Don .

The noise and smoke was Freon but not from a hose but rather a blow off . Man do I love the design of our coaches .

All is well . It was a relay . I was very happy with the work done by Southwest Diesel out here in St George and would highly recommend them . It is not the cleanest place nor did they have electric but there workmanship was 2 nd to none. Darren and Rex will not let you down . In fact I hear a Rally is held here and another PC member used there services maybe he can provide his thought on this Prevost recomended shop . Thank you again for the assistance . .