I have a VW Transporter T5 2007 with 2.5 TDi BNZ engine. I have the following fault code (among many):

p1503 Generator Terminal DF (Load signal) Signal Improbable.

This fault code gets repeated logged after about 5 minutes of driving at the same time as the ASR light comes on.

On SEATS (Also VAG group), apparently this is often a broken wire in the alternator loom, but I cannot find any information for VW T5s for this fault.

Please can any one advise what might cause this.

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    How many wires are on the alternator plug? How many volts is the alternator outputting? – Ben May 8 '16 at 12:43
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    It may be a two wire plug with L and DF terminals in which case DF is the terminal you want to look at. It should have ignition voltage (14+v) on it. If it doesn't unless you know where on the ignition circuit it connects to you're going to have to cut the wire loom open and visually inspect everything. – Ben May 8 '16 at 13:01
  • Thank you. I will have a look and report back. It wont be until next weekend now though. – Dib May 8 '16 at 19:15
  • @Dib what was the outcome of this? Did you manage to solve the fault or find out what it was? – jammypeach Aug 8 '16 at 9:35
  • Unfortunately no. I ran out if money repairing the damn thing and had to sell it at a huge loss. – Dib Aug 8 '16 at 10:37