Glow Plug Relay Wiring Diagram Mitsubishi L200

Closer

Thanks guys so far for all the help.

So I think I may have traced things down.

To start, I think I had the wires mis-labeled. The SRS and GP lights may have been backwards. You know how the SRS light comes on shortly when you turn the ignition on then goes out (presumably once the electronics inside the SRS module build up the required charge)? Well, I have been mistaking that for the GP light ever since I had the car it *seems*.

I tore the damn dash apart to trace this down.

The light I thought was the GP light was a pink and black/red wire. I traced it down to the passenger side footwell where it runs into the SRS and Seatbelt voltage transformer and condensor modules. Tracking down those part numbers and realizing they should have noting to do with the circuit in question, I quickly referenced Nfsjunkie91's schematic (thanks again!).

First, I want to point out that the actual GP indicator grounds itself through the cluster frame.

Next, I can a continuity test from the (newly discovered) GP light (black wire) to the black wire pin on the relay harness... bingo!

Next, I tested the bulb by grounding one side and jumping the black wire pin on the relay harness to 12v (relay unplugged, of coarse).. bingo!

This means the relay has NEVER been lighting the bulb ever since I owned this car!

Time to test the relay...

Before I begin, for anyone who comes across this thread, let me give the complete pinout (as of at least MY 1887)...

-------------------------------------------------
MB Part# 006 545 22 32

Control harness pinout:

(T )
(31) (LA)
(50) (15)

What goes where:
T == White wire, Temperature sensor, ties in to the engine temp wire in the cluster
31 == Brown wire, ground
50 == Purple wire, Starter wire - is energized when the starter is cranking
LA == Black wire, Lamp indicator to the dash (hence the LA!)
15 == Black w/ red stripe wire, start/run wire - energized as long as your ignition is in the "run" position.

Testing:

Apply 12V to large nut (where large red wire hooks to)
Apply ground to pin 31
Apply 12v to pin 15
-->> Relay should energize
-->> Terminal LA should provide +12v for your indicator lamp
Eventually, LA should become de-energized as the timeout is up and it is time to crank...

...this is where I am not sure of things...

I **think** the relay should stay energized until you crank the engine (apply 12v to pin 50) and release. At least that is how it worked for one person I watched bench-test one that LOOKED like mine on YouTube. Once he released the starter wire, THEN the relay kicks off. Mine, however kicks off after the timeout - period.

I think that, based on reading from coolant temp sensor, the relay should additionally stay on when the engine is cold for a pre-determined time period - not sure here.

-------------------------------------------------

So perhaps this is why it is so much more difficult to start in colder weather than others I have seen? My GP's were only coming on for a short time and kicking off... staying off while I cranked?

I suppose it is off to the scrap yard to find a couple.

Will post an update once I test a couple more relays.

- Dean

Source: https://www.benzworld.org/threads/190d-glow-plug-wiring-diagram.1892977/

Posted by: annavock1948esz.blogspot.com