Aircon Electrical issue. (1 Viewer)

[Tyson801]

Hi everyone I've recently decided to get my aircon sorted after 7 years of bearing the western Australia summers. I replaced Evap,dryer,compressor etc etc all new o rings and she has been re gassed and is holding fine. Now my issue has started when I went to press to AC on switch. No power is going to the AC clutch I checked the AC clutch was working by bridging 12v directly to it and she pumped ice cold air so the system is working fine.

But I have a electrical issue somewhere I've tested the AC cut off relay that's fine, I've then checked the negative switched AC coolant switch and that seems to work aswel, I've then found 12v in on the AC pressure switch and bridged it to try get my AC amp to switch on. Now this is where I'm having issues there is no power coming in to the AC amplifier nor is there power going to the relay above it. I've tried running a 12v cable directly to the ac amp with no change.

What could be causing this ? Also looking at my FSM wiring diagram im only meant to have 2 wires on my AC pressure switch but on my 80 I have 4.

Any help would be great.

 

[OffRoadScott]

Did you check the actual switch on the AIRCON button in the dash? Mine failed and I would have to hold it on and the AC worked fine once I released the button it would turn off.

 

[Tyson801]

Yes tested and looks to be working. ill re test it to be sure tho cheers.

 

[alia176]

There's a trinay pressure switch right in front of the battery. Once that switch detects the correct pressure it lets +12vdc power to go to the rest of the circuit. You can easily bypass this switch using a jumper to see if you get +12vdc where you're expecting it. This sw needs a min gas press to turn on, then turns off if a max press has reached in order to prevent over pressurizing the system.

 

[Tyson801]

There's a trinay pressure switch right in front of the battery. Once that switch detects the correct pressure it lets +12vdc power to go to the rest of the circuit. You can easily bypass this switch using a jumper to see if you get +12vdc where you're expecting it. This sw needs a min gas press to turn on, then turns off if a max press has reached in order to prevent over pressurizing the system.

Yeah I saw this the photo of the plug is my pressure switch a 4 wire plug that I've already jumped blue red with yellow red nothing happened when I bypassed this plug.

 

[alia176]

Is there 12vdc coming into that pressure switch?

 

[NeverFinis]

I've then found 12v in on the AC pressure switch and bridged it to try get my AC amp to switch on

Why do you need to bridge the power at all? AC Pressure switch should pass 12V through if the pressure is within min/max. Check the pressure switch, pins 1 and 4, with an ohm meter to see if you have continuity. If you do, then the problem is not there. You should see 12V on both pins if the A/C pressure switch is working.

Now this is where I'm having issues there is no power coming in to the AC amplifier nor is there power going to the relay above it.

If you have power coming out of the A/C pressure switch, you should have power coming into the A/C Amplifier at pin 3.

If not, you need to check pin 11 on connector IG2, and and pin 6 on connector EA1. IG2 is behind the glove box. EA1 is behind the left fender behind on the fuse box.

 

[Tyson801]

Is there 12vdc coming into that pressure switch?

Yes 12v at pressure switch blue red jumped to yellow red. Not picking up any power at ac amp or ac relay.

 

[Tyson801]

Why do you need to bridge the power at all? AC Pressure switch should pass 12V through if the pressure is within min/max. Check the pressure switch, pins 1 and 4, with an ohm meter to see if you have continuity. If you do, then the problem is not there. You should see 12V on both pins if the A/C pressure switch is working.



If you have power coming out of the A/C pressure switch, you should have power coming into the A/C Amplifier at pin 3.

If not, you need to check pin 11 on connector IG2, and and pin 6 on connector EA1. IG2 is behind the glove box. EA1 is behind the left fender behind on the fuse box.

No power at all anywhere on ac amp. Here's my ac amp plug. I believe black and white wire is ignition. No power anywhere in tried running 12v straight to it with still no success. No power to ac amp or the relay above evap box.

 

[Tyson801]

Why do you need to bridge the power at all? AC Pressure switch should pass 12V through if the pressure is within min/max. Check the pressure switch, pins 1 and 4, with an ohm meter to see if you have continuity. If you do, then the problem is not there. You should see 12V on both pins if the A/C pressure switch is working.



If you have power coming out of the A/C pressure switch, you should have power coming into the A/C Amplifier at pin 3.

If not, you need to check pin 11 on connector IG2, and and pin 6 on connector EA1. IG2 is behind the glove box. EA1 is behind the left fender behind on the fuse box.

Im not sure what ea1 etc means i can't see any of that on my wiring diagram. Or what ign2 is sorry mate can ya simplify it for me.

 

[NeverFinis]

I am using a 1996 FZJ80 EWD for reference. The connector ID, or the entire AC electrics, could be different if you have a different model.

EA1 is the first connector after the A/C Pressure Switch.

IG2 is the next connector, after EA1.

If you have 12V on the Y-R wire leaving the A/C Pressure Switch, you should have 12V at pin 6 on the EA1 connector.

If you have 12V at pin 6 on the EA1 connector, you should have 12V at pin 10 on the IG2 Connector.

Then check for power at Pin 3 at the A/C Amplifier.

 

[Tyson801]

Im not sure what ea1 etc means i can't see any of that on my wiring diagram. Or what ign2 is sorry mate can ya simplify it for me.

I've even tried bypassing ign2 completely by running 12v from pressure switch straight to pin 3 on ac amp. Still no power in out of anywhere else.

I am using a 1996 FZJ80 EWD for reference. The connector ID, or the entire AC electrics, could be different if you have a different model.

EA1 is the first connector after the A/C Pressure Switch.

IG2 is the next connector, after EA1.

If you have 12V on the Y-R wire leaving the A/C Pressure Switch, you should have 12V at pin 6 on the EA1 connector.

If you have 12V at pin 6 on the EA1 connector, you should have 12V at pin 10 on the IG2 Connector.

Then check for power at Pin 3 at the A/C Amplifier.


Yeah I'm not getting 12v to

I am using a 1996 FZJ80 EWD for reference. The connector ID, or the entire AC electrics, could be different if you have a different model.

EA1 is the first connector after the A/C Pressure Switch.

IG2 is the next connector, after EA1.

If you have 12V on the Y-R wire leaving the A/C Pressure Switch, you should have 12V at pin 6 on the EA1 connector.

If you have 12V at pin 6 on the EA1 connector, you should have 12V at pin 10 on the IG2 Connector.

Then check for power at Pin 3 at the A/C Amplifier.


View attachment 3836843

Ok. I jumped 12v across to yellow red not getting any power at all to ac amp or relay. Ran test from plugs to pins in ac amp and not picking up a single thing. Must be a broken connection somewhere on that line. Is the pressure switch the only thing feeding power to ac amp ?

 

[Tyson801]

I am using a 1996 FZJ80 EWD for reference. The connector ID, or the entire AC electrics, could be different if you have a different model.

EA1 is the first connector after the A/C Pressure Switch.

IG2 is the next connector, after EA1.

If you have 12V on the Y-R wire leaving the A/C Pressure Switch, you should have 12V at pin 6 on the EA1 connector.

If you have 12V at pin 6 on the EA1 connector, you should have 12V at pin 10 on the IG2 Connector.

Then check for power at Pin 3 at the A/C Amplifier.


View attachment 3836843

But even if i bypass ea1 and ig2 straight to ac amp plug im still getting no power to anything else

 

[NeverFinis]

Yes, power flows through the pressure switch to the AC amplifier. It is the only power source.

You shouldn't be running power anywhere. That doesn't diagnose anything, and you could potentially fry something.

This is the process, in order:

1. Test A/C Pressure Switch for Power, in and out, Pins 1 and 4.
2. Test EA1 Pin 6 for Power.
3. Test IG2 Pin 11 for Power.
4. Test Pin 3 at the AC Amplifier for power.

If you don't see 12V at any step, then the issue lies prior.

Let me know which step in the above you do NOT have power.

If you have power at the AC Amplifier, pin 3, then you move to other areas to test.

 

[Tyson801]

Yes, power flows through the pressure switch to the AC amplifier. It is the only power source.

You shouldn't be running power anywhere. That doesn't diagnose anything, and you could potentially fry something.

This is the process, in order:

1. Test A/C Pressure Switch for Power, in and out, Pins 1 and 4.
2. Test EA1 Pin 6 for Power.
3. Test IG2 Pin 10 for Power.
4. Test Pin 3 at the AC Amplifier for power.

If you don't see 12V at any step, then the issue lies prior.

Let me know which step in the above you do NOT have power.

If you have power at the AC Amplifier, pin 3, then you move to other areas to test.

No worries im trying to find EA1 and IGN2. I'll let you know how I get on.

 

[Tyson801]

No worries im trying to find EA1 and IGN2. I'll let you know how I get on.

Im getting power right up to what I believe is IG2 still tracing yellow and red wire back. From this plug it heads to behind the dash under the glove box where i am not getting power. 1st photo is plug where I'm getting power power after plug. Wire goes to glove box no power at glove box.

 

[Tyson801]

Yes, power flows through the pressure switch to the AC amplifier. It is the only power source.

You shouldn't be running power anywhere. That doesn't diagnose anything, and you could potentially fry something.

This is the process, in order:

1. Test A/C Pressure Switch for Power, in and out, Pins 1 and 4.
2. Test EA1 Pin 6 for Power.
3. Test IG2 Pin 10 for Power.
4. Test Pin 3 at the AC Amplifier for power.

If you don't see 12V at any step, then the issue lies prior.

Let me know which step in the above you do NOT have power.

If you have power at the AC Amplifier, pin 3, then you move to other areas to test.

Right. So i found i was getting no power to under the dash i cut yellow red wire where I was getting power and ran it to where I wasn't making a new line for it. Getting power to one side of the plug but not the other so I bridged it. Still nothing to anything. Im really stumped as to why no power is coming in at all.

 

[Tyson801]

Now for some reason my oil temp light stays on.

 

[NeverFinis]

I wouldn't be cutting anything. Really no reason to. Fix as you go, don't break as you go.

What year, model and engine is your 80 series? I might be able to locate the wiring diagram for it.

The key needs to be in the Ignition position.

Check the 10A Gauge fuse, which supplies power to the A/C Amplifier, through the A/C Pressure switch. That fuse should show 12V when the key is in the ignition position.

There is no relay involved in getting power to the A/C Amplifier, only the ignition switch.

The EWD states it perfectly:

WHEN THE IGNITION SW IS TURNED ON, THE CURRENT FROM THE GAUGE FUSE FLOWS THROUGH THE THE A/C DUAL PRESSURE
SW TO TERMINAL 3 OF THE A/C AMPLIFIER

We have been focusing on the EA1 and IG2 because they are in between the pressure switch and the A/C Amplifier.

What you are saying is you see power on one side of IG2, at pin 11 (I miswrote it as pin 10 earlier...it was late...), but not the other side.
It is Y-R coming into IG2, and Y-L leaving IG2. You are not seeing power on the Y-L line leaving IG2? Correct? Y- L = Yellow with a Light Blue stripe.

Or, you see power there, but not at the A/C Amplifier on the connector at pin 3?

 

[Tyson801]

I wouldn't be cutting anything. Really no reason to. Fix as you go, don't break as you go.

What year, model and engine is your 80 series? I might be able to locate the wiring diagram for it.

The key needs to be in the Ignition position.

Check the 10A Gauge fuse, which supplies power to the A/C Amplifier, through the A/C Pressure switch. That fuse should show 12V when the key is in the ignition position.

There is no relay involved in getting power to the A/C Amplifier, only the ignition switch.

The EWD states it perfectly:


We have been focusing on the EA1 and IG2 because they are in between the pressure switch and the A/C Amplifier.

What you are saying is you see power on one side of IG2, at pin 11 (I miswrote it as pin 10 earlier...it was late...), but not the other side.
It is Y-R coming into IG2, and Y-L leaving IG2. You are not seeing power on the Y-L line leaving IG2? Correct? Y- L = Yellow with a Light Blue stripe.

Or, you see power there, but not at the A/C Amplifier on the connector at pin 3?

Yes correct. But my wiring diagram shows its YR all the way from pressure switch to AC amp. I've used a multimeter and I'm getting no connection between ignition wire to the ac amp on start up or YR from glove box plug back. My rigs a 1993 hzj80 1hz.

Im not getting power at ST1 to amp or from pressure switch to AC amp im thinking there's a plug not plugged in somewhere or a major break at the firewall. I ran a wire from the IG2 plug YR to YR on the ac amp in hopes it was just that wire broken. I had power going all the way to firewall then under the glove box was 0 volts on any wire. Very strange one for me and abit out of my league I've decided to call a professional.

I've done everything I possibly can at this point I've booked it into a auto sparkie in a few weeks who specialises in landcruisers ill let you know the outcome.