Thread: Aftermarket A/C - 300Tdi dual cab

I'm afraid progress has slowed a little simply due to time restraints. The progress that has been made is pretty boring, being just wiring.

The first thing was to extend the wiring from the evaporator to reach the front mounted controls.

Fairly straight forward. I almost had the right colours - green becomes yellow (for the compressor solenoid):


The earth wire to the controls was originally separate and there was a spare socket in the plugs so I couldn't see any reason why it couldn't be included.



The earth wire from the controls bolted to the rear mount. I will running an earth wire from here to the chassis:


Now the tricky bit (for me anyway). I've placed two relays in the battery box (actually the relays from the original A/C system).

The first is for the compressor solenoid. My local A/C place which is completing the installation told me to just run "a wire" into the engine bay. I am going to assume they will activate both the compressor solenoid and the condenser fan off this wire. However, the relay is the type with two 87 terminals so the option is there to run two separate wires.

The second relay I am using to activate 12 volt power to the evaporator/fan power switch when the ignition is "on" (so the A/C can't be switch on when the engine is off). As to where exactly I'm getting the activation from right at this point isn't clear to me. I'm thinking I need to tap into one of the white wires that is the ignition switch side of the fuses for things such as the gauges, tail/reverse lights, etc. I'm really trying to avoid going up behind the dash because I'm very over feed wiring through there . Any advice or opinions will be gratefully received.

The 12V power to both relays is taken directly from the main battery (through fuses of course). Yes, I earthed the relays where the bracket bolts to the battery box, but this is just the earth for the activation of the relays, so only a small amount current. Please do tell if this isn't sufficient. I'm earthing the evaporator on the chassis where the batteries earth and the gearbox cross member bolts on, just outside the battery box

The relays and fuse box in the battery box:


Before I sign off, special mention goes to goingbush for completing his TD5 A/C installation today, in as little as a week and a half (!), with better than expected results. I'm more inspired now .

James.

Originally Posted by rainman

The earth wire to the controls was originally separate and there was a spare socket in the plugs so I couldn't see any reason why it couldn't be included.

Now the tricky bit (for me anyway). I've placed two relays in the battery box (actually the relays from the original A/C system).

The first is for the compressor solenoid. My local A/C place which is completing the installation told me to just run "a wire" into the engine bay. I am going to assume they will activate both the compressor solenoid and the condenser fan off this wire. However, the relay is the type with two 87 terminals so the option is there to run two separate wires.

The second relay I am using to activate 12 volt power to the evaporator/fan power switch when the ignition is "on" (so the A/C can't be switch on when the engine is off). As to where exactly I'm getting the activation from right at this point isn't clear to me. I'm thinking I need to tap into one of the white wires that is the ignition switch side of the fuses for things such as the gauges, tail/reverse lights, etc. I'm really trying to avoid going up behind the dash because I'm very over feed wiring through there . Any advice or opinions will be gratefully received.

Not being familiar with the Tdi electrics I cant help specifically but you are doing everything correctly, any
+12v IGN source will do, the energiser coil of the relay wont add any load to the system.

The 12V power to both relays is taken directly from the main battery (through fuses of course). Yes, I earthed the relays where the bracket bolts to the battery box, but this is just the earth for the activation of the relays, so only a small amount current. Please do tell if this isn't sufficient. I'm earthing the evaporator on the chassis where the batteries earth and the gearbox cross member bolts on, just outside the battery box

All looking good.
Dont forget about putting a High Pressure cut off switch in series with the compressor clutch, Worth asking your A/C guy about it, but he probably has that covered .

Great work !!

.

Originally Posted by goingbush

Dont forget about putting a High Pressure cut off switch in series with the compressor clutch, Worth asking your A/C guy about it, but he probably has that covered .

Would this be what the wiring and plug hanging off the top of the receiver drier is?

James.

Originally Posted by rainman

Would this be what the wiring and plug hanging off the top of the receiver drier is?

James.

Exactly, that is the pressure cut off switch.

on the factory Td5 A/C its hidden under the Evaporator,

hey rainman.....install completed yet?

Hi. Sorry everyone. Lots of "challenges"/things going on. Life........

Progress with the A/C is being made however. The Defender is, today, at the A/C place having the plumbing done. They say they'll need it for a few days, but I'll be sure to report back with photos and test results ASAP .

James.

flexible hose or pipe?

Originally Posted by weeds

flexible hose or pipe?

Ah yes. I did quiz him about that. It will be flexible hose like in goingbush's installation. Apparently that's all they use these days because the time and therefore the cost of bending up metal tubing is too prohibitive these days.

James.