Inoperative AC system
The AC wiring on a JDM Delica is poorly documented. Here's a diagram of the wiring near the battery and injection pump/cylinder head:
JDM Automatic L300 Diesel AC wiring.
In the battery compartment:
-thick White wire connects to a thick Black wire via a fusible link. This is the main power feed to the AC system.
Engine bay:
-Black Yellow stripe wire connects to the injection pump full throttle switch. This wire is normally earthed but at full throttle the switch opens, triggering the AC to cut out for about 10 seconds. AC will work normally if this wire is left disconnected.
-blUe Yellow stripe wire connects to a temperature switch on the radiator hose outlet stub on the head. Normally earthed, but opens if the engine overheats, disabling AC until the engine cools down. Connect this wire to earth: if it's disconnected the AC will think the engine has overheated and won't run.
-Black White stripe and Black wires to 2-pin plug: Idle speed increase solenoid. Operates the vacuum motor on the IP, pulling the accelerator lever a little, increasing idle speed.
-Not pictured, only on some vehicles: another overheat sensor, usually has a brown plastic plug. This one turns on the condenser fans when the engine gets hot to help cool it down. The sensor for this one is also in the radiator hose outlet stub, but because it works backwards (normally open, connects to ground when hot) if you plug the BY wire into this one the AC won't work. This optional, brown-plug wire can be left disconnected.
There are also fuses behind the glove box: remove the glove box, look for the white tubes. They sometimes just fail because of age/vibration, but will also blow if there's something jamming one of the AC condenser fans.
The AC wiring on a JDM Delica is poorly documented. Here's a diagram of the wiring near the battery and injection pump/cylinder head:
JDM Automatic L300 Diesel AC wiring.
In the battery compartment:
-thick White wire connects to a thick Black wire via a fusible link. This is the main power feed to the AC system.
Engine bay:
-Black Yellow stripe wire connects to the injection pump full throttle switch. This wire is normally earthed but at full throttle the switch opens, triggering the AC to cut out for about 10 seconds. AC will work normally if this wire is left disconnected.
-blUe Yellow stripe wire connects to a temperature switch on the radiator hose outlet stub on the head. Normally earthed, but opens if the engine overheats, disabling AC until the engine cools down. Connect this wire to earth: if it's disconnected the AC will think the engine has overheated and won't run.
-Black White stripe and Black wires to 2-pin plug: Idle speed increase solenoid. Operates the vacuum motor on the IP, pulling the accelerator lever a little, increasing idle speed.
-Not pictured, only on some vehicles: another overheat sensor, usually has a brown plastic plug. This one turns on the condenser fans when the engine gets hot to help cool it down. The sensor for this one is also in the radiator hose outlet stub, but because it works backwards (normally open, connects to ground when hot) if you plug the BY wire into this one the AC won't work. This optional, brown-plug wire can be left disconnected.
There are also fuses behind the glove box: remove the glove box, look for the white tubes. They sometimes just fail because of age/vibration, but will also blow if there's something jamming one of the AC condenser fans.
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