2017 Climate Control/AC IG1 No2 Fuse/MG CLT Relay

Any use in pulling those other relays and seeing what happens?

 

What wires in that plug to check magnet coil resistance? Green and violet?

 

Also OP, do live in the rust belt?

 

I do. However, If it matters, truck is frequently washed, garaged with climate control, it’s a 2017 with just over 30.000 on it. If we are getting into rust/corrosion talk, I’ve got none on the vehicle to speak of.

 

Idk. Someone would have to help me with that.

 

OP, what accessories did you add and where are they routed? Just curious.

 

I’ve got a flashing LED blue light bar, a dash cam, and an Escort radar detector high up on the windshield. They are all routed into the auxiliary lighter/outlet plug that is in the bottom of the center console. None of them draw much power, never blown a fuse on that circuit. I’m pretty sure that if that light bar wasn’t LED, it would cause problems.

The wires go into the headboard, down under the passenger side A-pillar behind the airbag, under the dash, and up under the center console to join in with that rear lighter/outlet power source.

I’ve also got a mount for a CB on the right side of my center console, but I only put it in for long road trips, and it plugs into the lighter/outlet plug that is on the front panel. So it’s a quick in/out kind of thing and doesn’t stay in the truck all the time.

Here is the write up on that install...https://www.tacomaworld.com/threads/windshield-accessories-wiring-write-up.500009/

 

From what I can see, removing that relay/turning off AC opens up two circuits, obviously related to the fuse being blown.
1st path goes to the magnetic clutch and straight to ground.
2nd path goes to the AC Amplifier, and not sure from where after that.

I would say check the path to ground with a multi-meter from the relay circuit that is on the coil side of the relay, but I'm not sure if it should be grounded or not.
So, if you've got plenty of fuses to spare, you can do the following:


Have truck set up normal (all fuses and relay's connected)
Disconnect the wires at the compressor and see what happens when you do turn on "AC".
-If it blows again, it's not the compressor


If it doesn't blow:
Disconnect the AC amplifier but reconnect the AC compressor and try again.
-If it blows now, your issue is related to the AC amplifier or beyond that.


We also cannot rule out that the new AC control assembly wasn't bad from the start.

 

I wasn’t able to disconnect the AC compressor. I tried, but the plug is at such an awkward position and so tight that I’d need to unplug it with pliers or something and I don’t want to mess it up by cracking the plug or pulling out a wire.

However, I did get my endoscope out. All the wires and connections look fine.

Is that a fuseable link that the red wire passes through under the compressor? I didn’t think those were used much anymore.

 

Try removing the driver-side fender apron with a clip remover (or similar tool that won't damage your vehicle/clips).
Then see if you can get access to the plug.

I don't see any reference to a fuseable link in any drawing or repair manual thus far.

 

That’s how I got these and got in there. Took that off and turned the wheels. There just isn’t enough room to get a good grip on the plug to disconnect it.

 

Ok, lets see if we can narrow it down without disconnecting the connector.

Remove the MG CLT relay
Disconnect the A35 plug for the air conditioning amplifier assembly
Disconnect the A1 magnet clutch assembly connector (might be able to be skipped)

Measure the resistance between:

-MG CLT-2 (Pin 2 of the relay slot) to A35-10 (Plug A35, pin 10)
--Should be below 1 Ohm

-MG CLT-3 to A1-1 (If you're able to get a probe in there to take the reading)
--Should be below 1 Ohm

-MG CLT-2 or A35-10 to ground
--Should be 10k Ohms or higher

-MG CLT-3 or A1-1 to ground
--Should be 10k Ohms or higher

If any are bad, it could be the harness or connector
If good, continue:


Reconnect relay, A35, and A1

Measure voltage at A35-10 to ground during the following conditions:

-Engine idling
--Should be 11-14v

Blower switch: LO
--Should be 11-14v

-"A/C" switch Off -> On
--Should be 11-14v then drop to below 1v

-Magnet clutch assembly (should engage when the A/C button is pressed):
--Should be 11-14v then drop to below 1v

If any are bad, it is likely the amplifier assembly BUT because the high current appears to be being drawn from your new AC control assembly, I'm not entirely convinced we'll see any issues while the fuse is blown and since it blows rather quickly we won't be able to catch it.

 

Had this issue today, similar, but lots of stuff shutdown.

This guy's post solved it!
https://www.tacomaworld.com/threads/replaced-battery-and-now-power-windows-don’t-work.603220/

Good luck OP!

 

You need to use a set of these. It will grip the plug and push down the release tang at the same time.

 

Not a fuseable link imo op. Looks like a heat shrink strain relief. Even if it was, it *might* not be that problematic.

 

Thanks, I will try this at some point today, it depends on when I have time between what I've got planned and the approaching thunderstorms.

 

Yes! Have those on my shopping list!

 

Stopped at the store this morning and got the extra long pliers. Worked like a charm. Unplugged the connector behind the compressor, and I also unbolted the ground on the compressor and cleaned it off just for “what if”.

Disconnected, no fuse blow. Connected, fuse blow.

I should mention however that with it connected, it’s the same as when the relay is out. Turn on the AC in the truck and it only stays on for about 3-5 seconds, then the AC turns itself off (the light on the AC button turns off). With the plug disconnected or the relay out, that action is the same.

Does that tell us anything useful?

 

Test resistance between SSR+ and SSR- at the compressor.
Should have a value of 160 to 320 ohms.

 

Coil is kaput.