Glow Plug Rail - Voltage = zero (1 Viewer)

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If anyone has any electrical experience on these old 2L-T wiring harnesses I would love to hear from them. I have swapped in a 2L-TII into an 1989 LJ70, and the harnesses and glow plug rails are a bit different.

If anyone has any experience, with the 2L electrical system I would appreciate any guidance.

1. Battery has 12.5 volts, Main Glow Plug Timer illuminates dash light for 2 seconds per shop manual,
Main Glow Plug Relay is "clicking" when keyed to "ON", However I am getting zero volts on the glow plug rail when keyed to "ON" and "START"

2. Glow Plug Current Sensor has (2) wires that run up to the glow plug rail. The black wire has 6 volts when keyed to "ON" at the sensor connection. However, When a load is put on this wire / I run a jumper up to the bus bar, voltage drops to ZERO on the black wire. Does this sound normal to anyone? Or does anyone kow what may be causing this?

3. The Red wire at the Glow Plug Current Sensor has zero volts. (not sure if this is correct, since the shop manual directs you immediate to cracking open the timer relay which is crimped shut).

4. Is it possible to damage the glow plug timer relay or main glow plug relay by trying different wiring combinations?

If anyone could point me in the right direction, I would greatly appreciate it.
Regards,
Don
 
Hey mate how'd you go? If you're still having trouble you can always simply bypass the current wiring and use 10.5v plugs as lostmarbles describes here: Which plugs should I be running - B, 2B, 3B, H and 2H diesels

Fixed delay 10.5V
Toyota 19850-68010, NGK Y-147T, Denso DG232
Bosch GPT218, Champion CH133, HKT PT 145

Here the busbar receives approximately the full battery voltage during pre-heating (because no glow controller or other type of resistor is fitted upstream). There is a glow-light (pre-heat light) on the dashboard that illuminates during pre-heating and extinguishes after a fixed time delay of between 15 and 20 seconds to tell you when to start cranking.

Owners often create a similar set-up that requires the same plugs (where the busbar again gets connected directly to the battery without any resistance device fitted inbetween) when their factory-wired pre-heating systems become troublesome. In such cases the dash-mounted momentary switch used to manually energize the glowplug busbar is commonly referred to as a “Wilson Switch”. And because no timer is used, the driver must estimate the pre-heat duration themselves.
A big advantage here is that the Wilson Switch allows the driver to smooth out a rough cold-idle by providing "After Glow". (The Wilson Switch can be used to re-energise the busbar once the engine is running.)

Super simple and reliable. In my case I used a 70 or 80 amp relay in conjunction with a resettable circuit breaker (as opposed to a regular fuse) in order to power 6x 10.5v glowies.
 
I finally did get it figured out. I put in a "Wilson Switch" and they are getting the voltage bypassing the Super Glow System.
Thank you for your response!
Don
 

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