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Discussion Starter · #1 ·
How do all.

Having a few no-start issues in -4'c weather with the car. It's on 116k and I believe original Glow plugs.

It turns over, but as it thinks it's starting, it stops. Gave up after attempt 7.

Tried once the ambient temperature had risen, started and ran. But, if it's cold and it does start, it starts on 5, maybe 4 or even 3 cylinders. Think of an old diesel train doing a cold start. But 20 seconds later, it's back on 6 and running perfectly.

This car has had a recent life of short journeys and DPF regens galore (Almost weekly). I've not had one regen issue, done an oil/filter change and also found a split hose on the DPF actuator unit on the Engine fuse box. So, if it was regening like crazy, maybe the glow plugs are completely battered.

But, the circuit. The 2 x 50 amp fuses are fine (F7 and F8), both are live and also testing the relays (R4 and R7), they click as required. Testing the live feed, it's there at the relay mount, as is 12v to the Switch feed, but there's also 12v at the ECU feed also. I'm guessing this switches to ground/negative to activate the glow plugs.

Is there a way to tell the car to activate the glow plugs but NOT start the car so I can check all voltages at the plug connections on top of the engine?

Also, the plugs themselves, how much of a bitch are they to get out?

Many thanks.
 

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Hi, I had the same problem, in my case it turned out to be the high pressure fuel pump, hopefully yours might just be the glow plugs. Phil
 
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🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
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Does sound like GP’s . Your best bet is to get to them and simply measure their resistance. Google it but expect a good one to be quite low resistance perhaps < 10 Ohms. Your duff ones likely to be open circuit.
 
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Discussion Starter · #5 ·
Does sound like GP’s . Your best bet is to get to them and simply measure their resistance. Google it but expect a good one to be quite low resistance perhaps < 10 Ohms. Your duff ones likely to be open circuit.
Do I need to get to them, or can I just measure from the connector on the top of the engine where it splays out to the 3 plugs per bank?
 

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🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
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Do I need to get to them, or can I just measure from the connector on the top of the engine where it splays out to the 3 plugs per bank?
The connector will be fine as long as you can trace the wires to each individual plug, so you’re measuring across each plug in turn
 

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MY 2012 XF S Portfolio Ultimate Black
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Do I need to get to them, or can I just measure from the connector on the top of the engine where it splays out to the 3 plugs per bank?
There is only one wire going into each glow plug with is shared between them all. The return is through the cylinder head. I.e. you could measure the resistance easily between the plug end and engine body. If you use wire end, you cannot tell easily if one or fwo has failed.
I highly doubt if you don’t see a DTC should there be a problem with the glow plugs as they are easy to be monitored by ECU.
If you have keyless entry, try pressing the brake pedal much harder and keeping the start button longer to see if it improves.
 
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