BAC Forum

General Boards => Technical Support => Topic started by: tomchase on May 31, 2018, 04:51:44 PM

Title: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: tomchase on May 31, 2018, 04:51:44 PM

My 05 Marquis dash ac quits working while driving then will restate after awhile. I'm thinking the circuit breaker resets after cooling down. Has anyone else had this problem or know w the location of this circuit breaker is? Thanks Tom Chase

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: Mike Shumack on May 31, 2018, 06:39:57 PM

Does the fan stop blowing too - or does it just stop blowing cold air?

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: tomchase on May 31, 2018, 10:18:31 PM

i Mike,

The fan stops blowing. We then turn the system off and wait a few minutes and turn it back on and it will stay on for awhile then shuts off again.
Thanks Tom

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: Mike Shumack on June 01, 2018, 01:27:15 AM

Sounds like a relay or breaker is getting hot and failing, then cools off and works again for awhile.
I could not find any diagrams specific to your year/model, but I do have a couple in my files (maybe its the same or close).

On the front bay, there are circuit breakers for the AC fan and other AC components. You should see if power is going through the breaker at the time when dash fan quites. Just test with a 12V test light and see if the output side of breaker has power.

I found two electrical diagrams (2008) dealing with Dash AC. Maybe something there will help.
Good luck.

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: tomchase on June 02, 2018, 02:05:15 PM

HI Mike,

Found a relay labeled condenser fan but none that said AC. Replaced that relay but problem still there. we are going to the Bend rally in July so I'll have Beaver Coach Sales and Service look at it.


Thank You.

Tom Chase

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: Steve Huber on June 02, 2018, 11:11:11 PM

Tom,
I don't have an 05 diagram, but the 03 Marquis diagram shows CB 29 in the front elec bay as AC Low Blower. Are you sure the AC is shutting down? If the fan dies it may seem like the AC is not working. Reason I mention that is there is an outside chance the fan ballast resistor is opening and then making contact when it cools down a bit. My 00 Marquis had 2, one for dvr and one for pass fans. They were located under the front cap on the dvr side. They had a small "cage" around them as they get quite hot.
Steve

Title: Re: DASH AC QUITS WHILE DRIVING WHEN WILL RESTART
Post by: Rick Vyncke on June 04, 2018, 08:52:09 PM

Tom,

I have a very similar issue on our 2005 Marquis.  I have discovered that ours only quits working when the blower runs in the maximum speed setting for awhile.  Like yours, if we turn it off for a few minutes it will restart.  We've also found that by running at a lower blower speed it does not stop working like it does when we run it on maximum.  Wish I could give you a better answer on how to resolve permanently but we've not yet figured that our either.  I will watch your post to see if anybody else has a solution for us.  Good luck to us both ;)