Climate Control Blinks then Dies
 

I have a 1999 Accord EX with manual climate control. A couple of months ago my climate control panel began to have issues.

At random all of the lights on the panel would go out and my AC would stop blowing cold air, although the blower was unaffected and still worked fine. After a random amount of time, ranging from a few minutes to a couple of hours, the lights on the climate control panel would come back on and the AC would kick back in.

Nothing else seemed to be affected other than the climate control panel.

I've searched the forums and there are several posts with the same issue, but if they were able to fix the issue they did not post the solution.

Several posters have pointed to the climate control unit as the likely culprit, with one suggesting that a faulty ignition switch may be to blame.

ATTEMPTED FIXES: I've cleaned the plug and connector on the climate control panel with contact cleaner. I've checked and cleaned the ground cable connector on the battery. I've checked the ground on the fuse/relay box which was good.

Nothing that I did made any difference and after a couple more weeks the panel no longer lights at all, but the blower works fine.

I'm ready to start replacing parts and my question is this:

Is the climate control panel the same thing as what people are calling the climate control unit, or is there another unit deeper in the dash that I just can't see?

No they mean same part. You need a shop manual to guide this job. Check links in Online Manuals post in DIY forum, or buy from automanualsource.com for $21.99.

I seem to recollect that some removed and repaired the circuit board, but may be mixing w/ gauge panel.

You should be able to find a used part on ebay or car-part.com.

good luck

Thank you for the speedy reply Texas, now to get one ordered!

I was able to find a post in another forum that detailed a repair procedure.

By jumping a wire from the positive leg of a capacitor to the voltage regulator I was able to fix the board, as were many others. Corrosion seems to be the culprit most of the time, and although none was visible on my board, there was definitely no voltage on the supply leg of my voltage regulator.

By soldering the jumper from the positive leg of C1 to the supply leg of the voltage regulator I was able to re-establish battery voltage to the regulator. My AC is once again working fine, although it's only been a couple of days since my repair.

Again, this was not my fix, but I'd like to share it with the forum, if that's okay.

Can I link to another forum (where the post and procedure are) or should I reproduce the other post here (with proper credit to the OP of course)?

go ahead and post the link

I replaced my control unit, but I did keep my old one. I would like to see the link to the fix.

Cool, it was a big help to me, glad I can pass it on.

Here's the link to the post, and although the post doesn't mention it BE SURE to cut a path through the black backing plate for the new wire to seat into. Once you have the plate off you'll see what I mean.

Also keep the exposed part of the wire that you will be soldering on as short as possible to avoid shorting out any of the surface mount components.

I have an electronics background, but it should be a simple repair provided that you pay close attention to the photos of the circuit board and attach to the right components.

The repair post is the 13th post down in the thread btw.

I had the same issues with my 99 Accord. The jumper wire fix worked for me. Thank you for posting.

Glad it helped someone else.

By the way, it's been several months now and my repaired climate control unit is still working fine.

Can you sen me the website, I am having the same issue, my lights on my 1998 honda accord quit working. I really love my old car and would like to get her up and going again. Thanks memeblu73@aol.com

P.s. any suggestions in this procedure would greatly be appreciated!

For some reason that link is dead. I found bits and pieces of info from other sites adn put them together for you. Basically, on the underside of the climate control board, just jumper the input (leftmost) leg of the78dl05 voltage regulator in the middle of the board to the positive leg of capacitor C1. That's it.
https://www.hondaaccordforum.com/for...-attempt-2-jpg

You can look up how to access the radio for detailed directions but in a nutshell:
- Remove plastic shroud/surround in center of dash
*remove 2 screws at bottom
*FOr third scres, it's hidden behind the clock. Using a thin bladed knife (I used a kitchen knife wrapped in a paper ticcue to avoid scratshing) or screwdriver, pry the bottom of the clock out and pull the unit out. Unplug the wires and set aside. Take out 3rd screw behind in dash. Lift shroud from bottom out.
- AC control unit is mounted to the back of the shroud.
*Disconnect the 2 wiring harnesses from AC control unit.
*Remove the 5 mounting screws and remove AC unit panel.
*Before mounting new unit, lug in the 2 wiring harnesses and check operation...you should be good to go if the original part was the failure.
- Replace pieces in reverse order.

This is the link:

Drive Accord Honda Forums - View Single Post - Heater / AC Control Replacement

It's dead Jim!

I'm not Jim. The link I posted looks good.

These are images of that person's post from the link.

The link to the other forum is in my post. The post in the thread is #13, and the guy did a great job detailing the procedure. Just checked the link and it's still good.

That was a Bones(Star Trek) reference. For some reason I was having trouble with the link on my pc.

That fix is still working for me, what a great find!

Redbull/Drocca


I am having same issue in my 99 Honda Accord. My AC is completely dead and Heater is blowing maximum settings Hot air. Fan knob is working but Climate control knob has no control over the Heater. No control unit's lights are functioning and no control over any of the buttons on the Unit(except the blower fan control knob)


The initial problem was exactly what is described here. Climate control unit used to blink , would make click-click kind of sound and then would go dead in 1-2 minutes. It would then work for the settings you had selected before it goes dead.


Now control unit blows hot air and pressing any button has no change.


I am wondering the wire soldering solution you have posted would work for my Car?


Please advise.


Thanks

Note: 1) I disassembled the unit, used contact cleaner to clean the circuit - No change.
2) I took my car to local body shop. They are asking me to replace Control Unit first. It means they are not very sure.

If you are got with soldering, then yes I would go with the jumper wire.

If not, a working one from "e-bay" or something like that....or a bone yard but one from a bone yard does not mean it is good....most yards will swap it out if you pull a bad one but the time and trouble of several trips might not be your thing.

Mine acted exactly like yours, at first blinking lights etc, then no lights, just blowing hot air(like some people I know).

This little jumper fixed the problem, I had cool a/c once again.

I no longer own that car, but it worked when I sold the car.

Good luck.

Sorry for the late reply. Provided that you have the manual climate control and NOT the digital climate control, the jumper solution should work for you. It worked for me for years, although I recently had to replace my CC unit for a different problem (potentiometer that regulates temperature became faulty).

Be sure to follow the directions carefully and if the problem with yours is indeed the same the issue should resolve.

I just used the jumper wire fix yesterday and it worked! I suck at soldering so if I can do this, anyone can.

same problem
 

The jumping of the wire worked perfectly. Thanks for the help

So I did notice an issue once I changed the buttons that control where the AC is dispursed. They do not change easily, it took quite a few times pressing buttons to get it to change. This is after I fixed using jumper

Could be the "mode motor" getting weak or binding?

You stated above that you were not good at soldering so I have to ask, the problem you now describe, was it present at any point prior or is it new? It may be that some solder is close to another lead on the board causing mixed signals if other suggestions don't work.

I think u may be right, wasn't the best soldering job. I'm probably just going to leave it alone since I always keep in on the same setting anyway. Just good to have cold air!

If my mechanic refuses to try this fix, will replacing the control panel fix the problem? It would cost over $300, but I have to have air conditioning.

You can easily do it yourself if I can. If you really want to replace the control panel, yes it will fix it but I wouldn't pay $300. The part is half that price and takes 15 min to install

I have a 1998 Honda Accord on which I replaced the control panel with a junkyard panel a few years ago. Recently the replacement panel failed too leaving the heater blowing full blast. While looking for a schematic I stumbled on this thread and tried soldering on the jumper. It worked perfectly. Thanks, guys!

You're welcome!

Glad this old post is still helpful!

Excellent!
 

My climate control was going off randomly, and I replaced all the LEDs, think I need higher powered led for circulation, and front defroster, as they stopped working again. Otherwise this hot wire fix has worked amazingly. Thank you.

I have done this and it still doesn't work.....I have power coming in and the ground is good.....I installed the jumper wire and still nothing....any ideas

you are in luck! same problem here, jumper wire did not work for me. However replacing all 5 capacitors did!. there is one cap however that was suspicious, the new capacitor I had was only half the size, so possibly the old one is a low ESR type. I went with the next best option and went to the next size voltage, the size was close to the old one. the rest of the caps matched fairly well. I got them on Amazon. I have tested it and the lights remain on and I can use my AC. seems to work. all junkyard ones will fail, if the jumper doesn't work or you want an actual fix, replace the caps. cap life is recommended to be replaced every 10 years, nobody does of coarse so getting 20 years out of these in hot and cold weather is impressive. I did not use the original nichicon brand, I needed to test out my theory first, would have been nice to get nichicon though