2.5 TDI Diesel Manual 9/96 On

The TDI model was with manual transmission only until 9/96, when an automatic was announced, however, these tables are for the manual transmission only. From 9/96 a different Powertrain Control Module (PCM) was introduced. This necessitated a change of PCM multiplug (C300), but the engine connectors C132 and C135 remained. 

The following tables are for the 2.5 TDI produced on 9/96 on. They should not be used for earlier models

On 9/97 a new connector C2643 replaced C304 on the diesel pump unit, but the pin numbers remained the same. 

The PCM multiplug, C300, is unique to this model. The location of the PCM is still behind the glovebox under the dash and is reached in the same way as the petrol models.

The engine connections are C132 and C135. They are also of a completely different design to petrol models, but are in the same location - on the driver's side engine bulkhead.

You will notice that the connectors are physically identical, but the wiring colours and pins-in-use are different. 

Engine Connections thru Engine connections.

Connections not thru Engine loom

Other sensors do not pass through the engine connectors and can be tested between the PCM connector and the unit itself.

The Diesel Pump Unit uses the connectors C304 up until 9/97, when you should look for the C2543.

Several PCM connections are made to the Accelerator Pedal Position sensor on the accelerator pedal support.

When testing the loom remember to disconnect both ends of the wiring before running the test.

Good Luck !