Diesel glow plug light working in reverse order

[mybrainhurts]

I've had a Suzuki Grand Vitara for a year. Renault 1.9 diesel.

I don't recall the glow plug light coming on at all until recently. The engine starts with no bother with no sign of the light but, when the engine is running, it comes on and stays on.

The only way to extinguish it is to momentarily switch the ignition off and on.

This is all arse about face, and I'm confused. Any ideas?

I get fault code P0670 glow plug control module control circuit/open.

[mad4amanda]

normally means a plug has gone. My merc does it in cold weather all the time, but as it`s DI it makes little difference unless -20. best to test each plug

[mybrainhurts]

[Jimmyarm]

If the glow plug light stays illuminated, there is a fault in the injection system.

The glow plugs are part of that system.

As you note, there is a fault relating to the glow plug control module....

[mybrainhurts]

Oh bugger...

Thanks

[mad4amanda]

Have you tested each glow plug yet? I very much doubt it is the control module more like a plug failed . At that age a control module may be as simple as a relay.

[mybrainhurts]

Not yet. Going to change them all, as four are only £20 from Opie, but just seen it's a bit of an arse to get to them and, as I can't get in my garage, I'm subject to this bloody incessant rain right now...

[mad4amanda]

I would test and only change those needing replacement as getting them out is not easy and can cause issues if they snap!
warm the engine and do a small amount say 20 degrees then leave it for a bit and do again

[t400ble]

Be ultra careful taking these out

Give them a spray with something prior a week before

[mybrainhurts]

Thanks...