A/C fail on big bumps

[Shaw520]

So where would a fella begin to look when the A/C shuts down triggered by a large bump in the road,.. obviously a loose connection or similar.... just looking for ideas on WHERE to start looking,. thank you

 

[wjburken]

I am assuming that you mean the HVAC control panel on the dash is shutting off but then comes back on when you push the button. If that’s the case, I would start by pulling the control panel and see if there is a loose connection on the back. Have you done any other work under the dash lately? Could also check to make sure the fuse is fully seated in its socket.

 

[Big Mama]

And never hurts to check your ground cables on both ends.

 

[Shaw520]

I am assuming that you mean the HVAC control panel on the dash is shutting off but then comes back on when you push the button. If that’s the case, I would start by pulling the control panel and see if there is a loose connection on the back. Have you done any other work under the dash lately? Could also check to make sure the fuse is fully seated in its socket.

I should have been more clear on that,...NO the HVAC system does NOT shut down,..heck it doesnt even flicker,.. it just stop blowing cold immediately and actually feels like its blowing hot air,... but all the indications stay as set.

 

[Shaw520]

Sounds similar to many of the "blend door' issues,.. except this issue is DEFINATLEY bump related.

 

[Doubeleive]

I would pull the control out so it is loose out of the dash, put some sort of padding under it, then go hit some bumps on purpose and see if it still occurs, if not you may have loose solder or something to that effect in the controller, if the problem still occurs then you know it's less likely to be the control and maybe a bad wire connection down by the pump.

one other thing to question on this, is does the control cut out completely? or does the fan/blower just cut off that could be a separate issue as well
or does the cold air stop being cold and just blows hot.

more detailed info will be needed to figure this out

 

[Doubeleive]

I should have been more clear on that,...NO the HVAC system does NOT shut down,..heck it doesnt even flicker,.. it just stop blowing cold immediately and actually feels like its blowing hot air,... but all the indications stay as set.

ok, so that would point me more towards the pump, I would start by checking the wiring harness at the pump, see if it is corroded or dirty, maybe jiggle wire while it is running and see if the pump shuts off.

I would still pull the control out though and pad it and take a drive just rule it out as well

 

[wjburken]

I should have been more clear on that,...NO the HVAC system does NOT shut down,..heck it doesnt even flicker,.. it just stop blowing cold immediately and actually feels like its blowing hot air,... but all the indications stay as set.

How soon after hitting a bump do you notice the warm air? How do you get cold air blowing again? Does it come back on its own and if so, how long does it take to return? Do you have to do something to the control unit? Do you have to hit another bump? Knowing this might help narrow things down, but it definitely sounds like a loose connection: at the control unit or in the control unit, at the blend door, at the compressor, etc.

I'm guessing that telling you to avoid bumps isn't an option!

 

[Shaw520]

How soon after hitting a bump do you notice the warm air?

Immediately

How do you get cold air blowing again?

Have to shut truck off and restart to get it working again.

I'm guessing that telling you to avoid bumps isn't an option!

not living in a state run by greedy politicians,..highest taxes,..highest cost of living,...********* roads.

 

[PG01]

not living in a state run by greedy politicians,..highest taxes,..highest cost of living,...********* roads.

Oh, New York....