A/C Electrical Helppppp!!!! Tried it all already

Hey Guys and Gals, I hope you're having a kickass day so far!!

I am looking for help and maybe I overlooked something. I want to say I have tested and replaced it all.

I have a 2007 Toyota Tacoma 150K. One day the A/C stopped blowing, just went out while driving. Now prior to all this happening, I did have the typical A/C issues with the Blower motor resistor going out and the connector showing signs of burnt pins. I replaced both connector and resistor, Worked fine for another couple of months.

Now the fan does not blow, on any setting. I took it to the dealer and the have misdiagnosed the problem twice. I was told it was the relays and fuses and need a new fan motor. I replaced them and still not working. I was then told It was a bad control panel unit so I replace that also and It is still not working. I was looking over the electrical schematic and everything works with the A/C amplifier, So I replaced that too and still nothing. I don't know what else to check. It is an electrical problem. When I turn the A/C on you can hear the engine side components engage and the engine RPM goes up a bit. So I know It is, not the Compressor or engine components that are Bad.

Parts Replaced:
A/C - Fuses and Relays under Hood
Blower Motor
A/C Control Panel
A/C amplifier

 

Get a multi meter and a circuit diagram and start working backwards from the fan until you find where the voltage is not being passed.

 

Sorry to hear about your AC problems.....I would have to agree. You will need to work backwards from the fan unit. I'm assuming someone check the fan unit to ensure it still works....good luck & keep us posted.

 

Did you look at the two wire connector that plugs into the motor itself? It is also subject to burning.

Here are the prints for the Blower and AC Circuit.

If you look you can see that the Blower motor should have AC power (12 VDC) on the Black wire with a Yellow Stripe when the blower is turned on any speed when the heater relay is energized.

Where I would start is start the truck and turn on the blower ( any speed ) and check for voltage at the Black wire with a Yellow Stripe. If you have 12 VDC at that wire then you know everything is working up to that point.

If you don't then you could have a blown IG1 NO2 Fuse. Check it with a meter don't depend on your eyes. You can't always tell a blown fuse. Also the ground wire for the heater Relay Coil is the yellow wire # 2 that goes through the AC Controller for a ground connection.

If you are getting 12 VDC and the blower still isn't running, then what you can do is to connect the white wire with a lavender stripe with a temporary wire to a good ground. If the blower runs (warning it will be full speed as the resistor will be bypassed). If the blower runs then you know the blower is working.

Now we are down to either the resistor or the ground wiring... All I can say here is to go through the circuit with a meter to check for broken or loose connections.

 

This is awesome and great info brother, Thank you. I have put a meter all over the place, but I will recheck these circuit and connectors. Also I don't know if this can be a clue of some kind. When the A/C went out so did the headlights. They only worked on Highbeams, The dealer replaced the relays and that started working again. I am going to use these prints and recheck it all. Thank you

 

If it's low on refrigerant, it won't turn on either. There's a pressure switch on one of the lines. Unplug it and check ohms on the switch. It should be closed, 0 ohms. If not, it's either a bad switch or no chilly juice in the system.

You can also jump out the connector and see if it turns on. I wouldn't leave it running though until pressures are checked in the system. You just want to see the compressor spin.

 

From the original post:

"When I turn the A/C on you can hear the engine side components engage and the engine RPM goes up a bit."

From his post I understood that the blower isn't working.

 

Ummmmmmmm, ya.

I got nothing.

I'll see myself out now....

 

No need to wear a bag! LOL

It's all good.

 

Any updates?

 

No easy answers with an electrical fault. Grab the multimeter, check every connection for power and ground, take nothing for granted, don’t assume even a brand new part is properly functioning.

I’d even considering running a jumper wire to the blower motor to make good and sure it works installed, just so you aren’t chasing your own tail.

 

What happens if you slam the glove box with the setting on high?

 

Hi! 2006 Tacoma a/c working only on high. I am so confused by everything I have read. Can anyone tell me exactly what to buy (brand and parts) to fix this permanently? Some people think it is fixed then it breaks a year later!
I bought a new blower fan and resistor with wire harness. Are these correct/enough for fixing the problem? See photos below. If not, please send me exactly what I need to buy!! Single mom trying to help son. Thanks!!

 

They look to be right in the picture. Look at the connector for the blower. Is one discolored? If so, then replace it as well. Look at the connector for the resistor as well.

Also, pull the HVAC controls out as there's a known issue there as well with burned connectors.

 

What is meant by ‘connector?’ It seems you are speaking of 2 different kinds.

 

I think he just means to check the resistor housing that is next to the blower plug for damage while you are down there.

Whenever you are bug hunting like this there is no such thing as being too thorough, IMO.

But I am completely daft and make tons of mundane errors that bite me later on down the process. I always get the big stuff right and then miss some "minor" detail that ends up biting me in the ass.

I have an 07 with 320k that I need to do this fix. Got the A/C only on high issue. Bought that same kit you got with the resistor from eBay/Amazon but just haven't put it in yet.

Good luck, this stuff can be maddening. At least you'll learn a ton about your truck's wiring scheme for any future issues.

 

The connector(s) I am referring to are what plugs into the blower motor, the fan speed resistor, and the HVAC controls. Unplug and look at the pins and sleeves on each end. If it's bad, one pin, or sleeve, will look darker and appear to have dust on it. If that's the case, replace both.

The HVAC controller will be brown/burnt up, on one of the connectors if the issue is there.

 

I was pretty sure that my connectors were burned up prior to writing this post. I just don’t know where to order the part from let alone what the proper name is for the connectors. I ordered a connector last week and it came in and said stereo. I don’t think that’s the right one! Lol Also, I read that the wire is burning out because something is too small and not large enough to hold the amount of amps coming through. If True, how do I buy a larger one so it won’t burn up again? I don’t know what size I have now or which part needs to be larger to handle the amp output. Thank you for your feedback!!

 

Break out your cell phone and zoom in... Look over that connector with a fine tooth comb and you will find a number on it. Five digits I believe. Bring that number to the dealership and they can give you the correct plug body and repair wires as needed

 

It isn't the size of the wires.
The loose fitting connections have a high resistance.
The High resistance expends energy.
The Expended energy takes the form of heat.
Heat burns the connector.

Replace the loose connector and pigtail wires.