Rover TDI heater plug

[DIYspanner]

When I first got the car, the yellow light for the plug used to go out after a few seconds, now it takes about 10 seconds.

Time for a new plug perhaps?

 

[Burnerman]

Possibly, but the time interval may be influenced by the ambient temperature of the engine.
If the engine starts up ok, I wouldn't worry too much.
John

 

[DIYspanner]

Thanks for that.

In order to test the plug, is it safe to take it out and short it across the battery with a bit of wire?

 

[Burnerman]

Hmmm some folks say it would be, and it sure would glow nicely on test....however, some plugs need a pulsed supply and others - usually rated at 11v - don't take kindly to be powered up for too long!
So long as you don't overdo it, etc....
Personally I use a meter set to measure resistance - a good plug has a resistance of around 1 ohm only.
John

 

[DIYspanner]

Thanks Burnerman

I'll test with a multimeter.

 

[alan333]

An easy test is to remove the wire connectors and take a long screwdriver or similar and touch it onto the top of the heater plug thus extending the connector height to an accessible place. Then take a jump lead or similar from the poz battery and skiff it off your screwdriver. If it's a juicy spark the plug's ok, if it's a wimpy spark or nothing then the plug's kaput.

Only do this if you're competent enough tho.