AC switches internittent - ZR-1 Net Registry Forums

WARP TEN · 08-28-2013

Yesterday I was running the A/C (95 degrees in Chicago) and for a while a few of the switches on the A/C console didn't work. The temp change button wouldn't work except to increase the temp (by the time I was done experimenting it was up to 82 degrees). Also the Off button wouldn't work. Tried a few of the others and they seemed to work. Later in the day they all seemed to work. Am I facing the imminent failure of the A/C control head? Car has only 24k miles. Maybe switches are giving up due to old age? (My pass window switch is also getting a bit iffy. At some point soon I will pull the door panel to see if I have a loose connection.) Has anyone experienced the A/C switch issue and is there a solution? -- Bob

Route 66 · 08-28-2013

Quote:

Originally Posted by WARP TEN

Yesterday I was running the A/C (95 degrees in Chicago) and for a while a few of the switches on the A/C console didn't work. The temp change button wouldn't work except to increase the temp (by the time I was done experimenting it was up to 82 degrees). Also the Off button wouldn't work. Tried a few of the others and they seemed to work. Later in the day they all seemed to work. Am I facing the imminent failure of the A/C control head? Car has only 24k miles. Maybe switches are giving up due to old age? (My pass window switch is also getting a bit iffy. At some point soon I will pull the door panel to see if I have a loose connection.) Has anyone experienced the A/C switch issue and is there a solution? -- Bob

I am having the same problem with my A/C/ If you find a fix would you please let me know. With a PM....Thanks Route 66.

Franke · 08-28-2013

Sounds like a poor connection since it seems to change with heat. I would check ground to the control head and AC Programmer module or the connectors themselves. Page 8A-68-0 In the FSM.

WARP TEN · 08-29-2013

Quote:

Originally Posted by Franke

Sounds like a poor connection since it seems to change with heat. I would check ground to the control head and AC Programmer module or the connectors themselves. Page 8A-68-0 In the FSM.

Yes Franke, when all else fails I suppose I should read the manual

. That is a good suggestion-maybe grounds but I am confused by the fact only a couple switches are affected. The "Off" switch doesn't work but once in a while with a hard push it will. I am afraid to touch temp so I have it set at 74 degrees and use the fan switch to slow things down. All switches but "Off" and "Temp" seem to work. At some point when I get a chance I will start serious diagnosis. Thanks--Bob

John Boothby · 08-29-2013

You need to remove the a/c control head and then remove the face and clean the button contacts. I did this with mine and it works perfect now. Use an electric contact cleaner and q-tip to clean. Easy to do.

GOLDCYLON · 08-29-2013

Quote:

Originally Posted by John Boothby

You need to remove the a/c control head and then remove the face and clean the button contacts. I did this with mine and it works perfect now. Use an electric contact cleaner and q-tip to clean. Easy to do.

Concer with this recomendation. Cost to try is almost nothing as well

Franke · 08-29-2013

Yep. What John and Gold said. Hope that fixes it for ya. 20 plus years of service can cause dirty contacts. Bet the door window switch is the same.

WARP TEN · 08-29-2013

Thanks to all of you. I think I will be cleaning switch connector contacts in the near future. It does sound like the logical explanation. And as you might imagine, the A/C seems to be working today. --Bob

Pete · 08-30-2013

Bob,clean the contacts, Bob G. had the same issue in his low mile 1994 Z took it apart and cleaned the contacts and works been just fine for 3 years.

Don't you just love low mileage Z's

Pete

scottfab · 08-30-2013

Quote:

Originally Posted by Franke

Yep. What John and Gold said. Hope that fixes it for ya. 20 plus years of service can cause dirty contacts. Bet the door window switch is the same.

As with so many of the issues that come up on the car this is an old and repeating one. Yes by all means clean the contacts. The reason they fail is oxidation. The metals used are a cheap tin alloy. Cheaper than it should have been.
Coat them with dielectric grease when re-inserting the head contacts.
This keep oxygen away from them prolonging the time it takes to oxidize. It's not the buttons it's the connector.
There is another thread somewhere on this but I'll restate the cause from the perspective of a classmate of mine who holds a PhD and 26 patents in the field of metal to metal contact issues. It is the result of dendrite growth and oxidation.

08-28-2013	#1
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,151	AC switches intermittent Yesterday I was running the A/C (95 degrees in Chicago) and for a while a few of the switches on the A/C console didn't work. The temp change button wouldn't work except to increase the temp (by the time I was done experimenting it was up to 82 degrees). Also the Off button wouldn't work. Tried a few of the others and they seemed to work. Later in the day they all seemed to work. Am I facing the imminent failure of the A/C control head? Car has only 24k miles. Maybe switches are giving up due to old age? (My pass window switch is also getting a bit iffy. At some point soon I will pull the door panel to see if I have a loose connection.) Has anyone experienced the A/C switch issue and is there a solution? -- Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough" Last edited by WARP TEN; 09-05-2013 at 01:31 PM.

08-28-2013	#3
Franke Join Date: May 2013 Location: Beaver, PA Posts: 515	Re: AC switches internittent Sounds like a poor connection since it seems to change with heat. I would check ground to the control head and AC Programmer module or the connectors themselves. Page 8A-68-0 In the FSM.

08-29-2013	#5
John Boothby Join Date: Jul 2005 Location: Las Vegas, Nevada Posts: 775	Re: AC switches internittent You need to remove the a/c control head and then remove the face and clean the button contacts. I did this with mine and it works perfect now. Use an electric contact cleaner and q-tip to clean. Easy to do.

08-29-2013	#7
Franke Join Date: May 2013 Location: Beaver, PA Posts: 515	Re: AC switches internittent Yep. What John and Gold said. Hope that fixes it for ya. 20 plus years of service can cause dirty contacts. Bet the door window switch is the same.

08-29-2013	#8
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,151	Re: AC switches internittent Thanks to all of you. I think I will be cleaning switch connector contacts in the near future. It does sound like the logical explanation. And as you might imagine, the A/C seems to be working today. --Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"

08-30-2013	#9
Pete Join Date: Dec 2003 Location: Chicagoland,IL Posts: 2,667	Re: AC switches internittent Bob,clean the contacts, Bob G. had the same issue in his low mile 1994 Z took it apart and cleaned the contacts and works been just fine for 3 years. Don't you just love low mileage Z's Pete __________________ '91 #1635 PoloGreen 350 LT5 11.09 @ 129.27 11.04 @ 128.86 474RWHP 400RWTQ http://www.youtube.com/watch?v=SFNFOhGGlR4 http://www.youtube.com/watch?v=ZlRIOMwaDYY https://sites.google.com/site/peteszr1garage