glow plug light flickering and clicking sound - glow plug relay problem? 1HD-T (1 Viewer)

[matyw]

Hello,
I can't seem to find a thread that helps me resolve my issue of the day.
I have a 1993 80 series from Panama LHD with 1HD-T.
I have had it for about 5 years and have never changed the glow plugs and never had trouble starting it and still don't even on cold days.
Recently the alternator was dying with all dash lights on and that is when i noticed the clicking under dash on the drivers side. $750 later and a new alternator i am left with the clicking and flickering of the glow plug light.
My guess is that i need to replace a relay. Anyone have an insight or part number.
Many Thanks
Matt

 

[IanB]

Check your grounds, as far as I know the glow plug dash light only comes on when the ECT sensor reading is below a threshold and you switch the key to the ACC position before starting. I don't believe there's any feedback function to alert you of issues with the system. If the system appears to be flicking on and off in this situation, I'd say it's not getting a constant ground from somewhere. Given the recent alternator replacement, that's where I'd start looking.

 

[matyw]

Hi IanB,
Thanks for your reply.
I think you may be right about the bad ground. I can't find where the bad ground is. There is a relay inline of the electrical wires very close to the battery (attached to the positive terminal) marked glow plugs and then it goes into a wire loom and meets up with another loom from the underhood fusebox. It then disappears below. Not sure what to make of it or where to check next.

 

[Squash]

Plugs are grounded by the engine block.
Power is supplied by a bus bar to all six glow plugs. As this is LHD yours is on DS

I would start by getting on top of engine and identifying the positive lead from fire wall to bus bar, once this is known check to see that all connections to individual glow plugs are snug and free of any potential shorts like someone's misplaced wrench, screw driver etc.
The bar is a silver coloured strip of metal, you do not want this grounded to anything but the tops of your glow plugs.

You could further trouble shoot by disconnecting the Positive lead to the bus bar insulating this from any ground and turning on your key to see if things are normal.

 

[matyw]

Hi Squash. Thanks for the info.
I will have a look tomorrow and see what I can find out.
Cheers
Matt

 

[Tapage]

I'll put my bet on faulty ground ..

 

[Bigherm22]

Ever solve this one? Same thing just started in my '96.