Diesel engine wiring

Browns are Earths.

T3 3 pin connector

The thickest (10 guage)red goes from the alternator to the positive on the battery black live with ignition fuel cut of solenoid on the fuel pump. feed to glow plugs is red (heavy duty thick wire) temperature sender for glow plugs is white blue feed to temperature sensor for the auxiliary pump is brown red

red is for auxiliary pump positive side and brown red for the negative.

The T7a 7 pin round connector in the black box T7a 7 Oil pressure switch High revs yellow T7a 6 Red white is for the auxiliary pump solenoid T7a 5 W connector on alternator (rev counter) is green on the forward end then red white to the alt T7a 4 earth T7a 3 blue/green coolant shortage level sensor T7a 2 yellow/red coolant temperature sender T7a 1 blue/black is low pressure oil sensor low revs (note same colours used for reverse lights) T3/1 black to D connector on alternator (charging light on dash)

T7 Round 7 pin connector in the black box that handles Lighting

T7 7 T7 6 grey/red tail light right T7 5 grey/black tail light left T7 4 black/blue reverse light T7 3 black/red brake light T7 2 black/green rear right turn signal T7 1 black/white rear left turn signal

grey/white is fog light single connector in black box

There is a Black box on the left hand forward side of the engine bay. This contains most of the wiring as it comes from the front of the van in the loom to the rear. It also contains a 50 AMP strip fuse for the glow plugs and the solenoid for the glow plugs too. It's a good idea to keep the cover for this box as once its lost moisture gets in here and causes grief.If you have a turbo engine there is an auxiliary coolant pump that fires in if the engine stops and the engine is still hot (>107 deg C) and circulates coolant until the engine cools down a bit. (Syncros also have a fan blower on the turbo for extra cooling) There is also a round 7 pin connector that carries the feeds for the rear lights There is also an Earth point on the left hand side on the engine bay with about 4 Earths connected this gets crudded up and corroded its a good idea to clean it up and remake the connection or extend the earths neatly back to the neg post on the battery. This handles some important stuff like your coolant level sender.