Just realised I've spent nearly two hours on the phone to my mate and he has taught me ever such a lot about how to test and what to expect where, potentially (no pun intended!).
Having picked the wiring diagram to pieces, I reckon that one of the relays has high resistance. I am getting 9V at the fuel pump. That could be mice chewed insulation and water ingress causing high resistance or high resistance at Pin 4. However Pin 5 feeds F11 which in turn feeds the air flow sensor (Air Mass Meter), the EGR Valve and the Turbocharger Pressure Regulation Solenoid Valve.
The fault codes were:-
0110 Inlet air temperature signal: Short circuit to + or open circuit.
0215 Injection system supply relay: Short circuit to earch or open circuit
0403 EGR Electrovalve: Short circuited to earth
1402 EGR Throttle Electrovalve: Circuit in short circuit or to earth
1301, 1208, 1233 and 1253 are all supplied from one of the relays in 1304 via F11 in BF01. The relay is therefore the common denominator. 1208 is the diesel injection pump and the common wire goes to the fuel cut-off solenoid.
The earth side of all these solenoids is via the ECU.
So my plan of action for next weekend is:-
1) Check F2, F4 and F11 in BF01.
2) Check pins 3, 11, 15 and 8 of 1304, Double relay.
Can anyone tell me if the rear of the connector can be back probed? The reason I ask is that the bonnet was left open for around 3 months and the ECU box cover was missing. Maybe it rained in trickled down the connector and has caused some correction with the double relay. We've had some pretty frequent heavy rain.
3) Substitute the double relay out (my mate apparently has a spare one kicking around miraculously)
4) Check if 12V and fuel pump and try to start. If not take temporary direct feed.
5) Check for 12V on feed side of 1310, 1233, 1253 and 1277. If OK, check for 0V on ECU side. If open circuit, check wiring back to ECU.
I'm no expert at electrics.
Does this seem a reasonable flow of checks to make?
Also, what is the correct procedure for getting the transponder to pair to the key please? I don't like having to waste valuable battery energy cranking to get the transponder light to go out. If I can get the car running again, I will have to buy a new battery for it as I am using my S1 battery as a donor every time I visit my mates.
Sorry for all the questions.
You guys have been a godsend! I've learnt SO much today. Now just got to retain it...
Forgot to mentioni the external temperator sensor in the cabin clock was showing 64degC today. I think it might take this information off Pin 4 off 1310?
Last edited by GiveMeABreak on 14 Feb 2020, 22:17, edited 1 time in total.
Reason:Removed Quote - Previous post
No, 1310 is the combined MAF & inlet air temp sensor, this only measures the temp of the air being sucked into the engine. The external air temperature is measured by the thermistor in the LH door mirror assembly.
Would I be right in saying the 8630 is somewhere behind the glovebox in the passenger footwell?
Also, should I get a voltage reading from Pins, 5, 6 and 19 if the key has correctly communicated its code to the transponder?
In the Diagnostics manual for Coded Anti-Theft IIRC, you can have a fault where the transponder light goes out on the dash but the car will still not start.
On that note, I'm going to get up there and see if I can get it started this week. Wish me luck please!
8630 is the CPH and is located behind the glovebox.
Pin 5 is ignition switched live. The other wires may be communication wires & may not have a definite live, they may be pulses.
I'm not sure what that is of - the CPU has multiple connections to the Alarm system (if fitted) and the Central Locking as well as the Immobiliser, so if that is the CPU in one of the pictures, how many socket connections does it have? Sometimes there may be more than one connector fitted into one large socket.
If it is the CPU ECU (picture on the left) then that is obviously longer than a 27 pin connector, so likely does have one or more separate connections form the immobiliser, the Alarm and the Central locking as I mentioned.
