Heater control ground location?
 

Our Accord has a bad heater control. There's power but no continuity. Can somebody tell me where the ground is? I really hope it's not the wire itself as I really don't want to dig through the harness. Thanks in advance!

What year, model trim?

You can include you car's info. in the signature or each thread.

1998 Accord LX, 2.3L VTEC/4AT.

G401 is the gound for the heater control "panel"....it is also the ground for many other things so it is a bit strange that more than just the heater control panel is not getting ground to "pin #9" on the connector for it :shrug:

Behind the left kick panel, you should see a bolt to the body with a mess of wires connecting to it.

These are some photos of G401. It is above the kick panel; so, it is not necessary to remove the kick panel to see it. You may have to remove the dash under-cover though.

https://www.hondaaccordforum.com/for...4&d=1432388818


http://s3.amazonaws.com/f01.justansw...23636_g401.jpg

:) The man with the best pic's......

I agree with Poorman212 that it is it is also the ground for many other things so it is a bit strange that it is not more than just the heater control panel with issues.

Further testing is needed. Where is there no continuity (e.g., which wires, power or ground, color of wire(s), etc.)?

It's the black ground wire to the #9 pin on the heater control connector.

The leads of the volt meter should be long enough for you to check continuity from Pin #9 of the connector to the ground bolt (g401). No sure what you were using before, could have been a weak coonection.

Note, the manual HVAC control panel on the 6th gen Accord's will go bad. There are a few write ups on here on "how to repairs".

Okay, so I found the G401 and checked again for continuity, and there was nothing.

Basically what has happened is that it has slowly gone bad. It started out being really flaky and it wouldn't always work, and the lights that were on at that particular moment on the control panel would flicker and we would hear a clicking/snapping sound that went along with the flicker. Then it totally died a few days ago, and what really sucks is that it's stuck on hot air, so always blows hot air even with the dial set to cold. NOT something we want to be stuck with when the summer weather hits!

Two things I'll throw out.

1. Until resolved, under the hood remove the cable from the heater control valve and manually close it.

2. Run a new wire from G401 to Pin #9 and see what you have then? If that "temp" ground brings everything "back to life"...the decision tree goes from there. If that "temp" ground does not bring things back to life there is more testing to be done.

I jerry-rigged a temporary ground wire from the pin in the connector to the G401 and still no continuity. Could the connector be bad? Or does the unit have to be plugged in to check for continuity?

PLEASE don't take this wrong but something just isn't adding up here.

You run a wire from G401 to Pin 9 and still do not have continuity through the wire?

When your meter is set to test for continuity, touch the two leads together....what does the meter display?

No, you're fine. I agree that something's not adding up and I'm rather confused. When I touch the multimeter probes together it registers 0v. The continuity symbol is the one that looks like an arrow and a positive sign put together, right?

EDIT: I just did some research and found out that the symbol I referred to above is the diode check symbol. I discovered that the continuity check symbol is the one that looks like a Wi-Fi symbol. Went and tested the wire again and found that there is continuity in the ground circuit. I felt like such a dingbat. Lol Unit shot?

Just to double-check it is not a power or ground issue:

1. At the rear of the heater control panel is a 22P green harness connector. Unplugged that.

2. With a voltmeter's red lead touching the Wht/Yel wire terminal (terminal no. 3), touch the voltmeter's black lead to body ground (for example, metal bracket or unpainted bolt on car's body). Is there voltage and what is the voltage measurement?

3. If there is voltage in step #2, then with voltmeter's red lead still touching the Wht/Yel wire terminal, touch the voltmeter's black lead to the Blk wire terminal (terminal no. 9). Is there still voltage and is it about the same measurement as in step #2?

4. Next test for voltage at the Blk/Yel wire terminal (terminal no. 2) with the ignition switch in position II (ON). Voltmeter's red lead to Blk/Yel wire terminal and voltmeter's black lead to body ground. Is there voltage and what is the voltage measurement?

Test 1: 12.48V. Test 2: 12.54V. Test 3: 12.20-12.25V.

I went and found this thread (https://www.hondaaccordforum.com/foru...s-49643/page2/) and soldered the wire between the two points shown in the picture, and it works again! The only issue left with it is that three of the lights don't work. One of them flickers when selected, and two of them don't work at all.

The lights not working may be due to bad through board vias. See post #5 in this thread:

Heat/AC Control indicator light - Honda-Tech

Checked out the link and made the repairs outlined in post #5. The light that flickered is now working properly, but one light is still out and the other that was out flickers. It even stays on and flickers when the car is shut off.

Okay, so I resoldered the jumper wires and now all of the upper lights work as well as the A/C and rear defroster indicators. But now the recirc indicator does not light at all. Tried resoldering that wire a couple of times and it still won't work. Could the bulb be shot, or am I just going to have to replace the whole circuit board?

Bump. Anyone? I don't mean to seem impatient, but I'd like to try and fix this without having to get a replacement board, if at all possible.

If the you've touched up the board and got a few things working but still can't get everything going it might be time to get another one.

You might try a bone yard (www dot car-part dot com) or ebay instead of the dealer to keep the cost down.

Yeah, that's what I figured I would have to do. Got a used one from the pick-and-pull and now everything works great.

Good to hear and THANK YOU for the follow up. Too many times we never know the end of the story :(

Glad to hear that a used unit resolved the problem. I had a similar problem a few years back (lights and AC coming on and going off, and eventually just staying off) with the climate control in my 99 Accord. The jumper fix worked for mine and it has been working since.

Having said that, it seems that the potentiometer that controls the temperature for mine has lately become fouled or faulty. Guess it's the pick and pull for me too since I doubt that there is a way to clean the contacts.