Help with Glow Plug Control module override switch

[richardharris51]

Hello Folks,

I am having a real bad time of it starting a td42 gq patrol 1992.


I have narrowed it down to the glow plug control relay not letting the glow plugs glow long enough. (literally on a cold morning will only stay on for 3s)

I found this on an old post:


"The glow plug control unit for the GQ TD42 doesn't run the tacho.

If you want to bypass the controller and set up a manual switch for the glow plugs.

Just unplug the unit, find the Green wire with a White trace (pin 6) and the White wire with a Green Trace at the plug (pin 1), splice into each of these and run both wires to your manual momentary switch.

When the ignition is on and you push the switch the glow plug relay will turn on and supply power to the glow plugs"


BUT when i slodered my switch in i did not work.

so now i really need some help.

Has anyone done the manual overide switch, am i missing someting.

thanks

Richard

[thebrod]

Hi Richard

I have done an override switch on my ZD30. Not sure how similar to yours this will be but here goes.....

The Relay has 4 wires going into it. Two Big wires, that are the 12 volts that the relay switches on for the glow plugs, a smaller 12 volt +ve wire and the green/white wire which is the earth. The ECU closes the earth (not the +ve as I originally thought) to the relay to switch on the glow plugs. All I did was splice in a new wire to the green/white wire that goes to a momentary switch and then to an earth point. All the original wiring remains plugged into the relay so the ECU wont be tempted to throw up any error codes thinking that the glow plug relay is not working. So the ECU still controls the glow plugs as normal, but I can press the momentary switch and activate the glow plugs if I want/need.

Hope this helps...
Adam

[richardharris51]

just to confirm did you splice into the wires by the glow plug control unit (mine is green and located by the pedals in the right side wall)

or did you splice into the wires up on the second relay under the bonnet?

as my car is the GQ i do not think I have the ECU to contend with.

Any one else done this on a GQ or any further advice.

otherwise I am going to have breakfast and try and bypass the glowplug control unit all together

[thebrod]

Hi Richard
I spliced into the wire on the big relay under the bonnet.

[richardharris51]

right well this is my problem then because i spliced into the glowplug control unit in the footwell.

however i am still not sure if it will be the same for our different models, thanks for your help.

[richardharris51]

in the end i did splice into the right lead yesterday, always the way!!

this is what i did for a 1992 GQ td42, and it all works fine now:

1) took off kick panel near drivers door to reveal the green glow plug control unit

2) spliced into the green and white wire that comes out of the glow plug control unit. Connected this to one side of the switch

3) to the other side of the switch i ran constant power

BAM thats it. I used a narva button switch so i don't accidentally hit it with my hand etc.


Thanks again for the help

[Yendor]

It not the White wire with a green trace it's the Brown wire.

The Brown wire is the ignition feed.

The Green wire with the white trace connects to the glow plug relay.