You should definitely check that your controller is correctly wired IN SERIES with your "parallel-connected glow plugs" rather than being wired in parallel with them (as though it were an extra glow plug).
That would imply that the glow controller has a path to ground that doesn't go through the glow plugs. Easy enough to test this, just disconnect the heavy wire at the bus bar (ensuring it doesn't short circuit to something) and see if the glow controller lights up during a glow cycle.
However, if that's the case the controller would have showed signs of life when the 14v plugs were installed.
Thanks. Looks like the correct relay and the correct wiring configuration. I thought you might have a 24v relay and possibly a swapped wire. The S terminal in your 12v relay doesn't do anything but it's functional on the 24v models.
I think the question here is: WHERE do those wires go?
If one of them is to ground you have an indicator light that shows that there is voltage on the busbar.
You have to check the wiring from the relay to the controller to the busbar.
I'm with Tom thinking that the/a PO rewired the system to get it going.
In my case, my BJ40 was re-wired to bypass the burned out controller and the PO put the full 12V on my (poor) 8.5V plugs. One was burned out, one was high ohms and the other two were barely alive.
To summarize this topic, Jesper was experiencing a problem where his glow controller did not light up at all. Discovered he had 14v glow plugs installed. Replaced the glow plugs with 8.5v plugs and the glow controller appeared to get too hot too quickly. Replaced the glow controller with the correct stock Toyota part. Glow controller still glows too hot and too quickly.
I have tried to figure out a way that the/a PO could have screwed up the wiring so the glow controller wouldn't glow at all with 14v plugs but will glow too quickly with 8.5v plugs. I can't figure out a schematic that makes this chain of events possible unless something changed with the wiring since the beginning of the topic.
Edited to add: the bus bar voltage was measured at 10.35v when the 14v plugs were in place. Jesper - could you measure the busbar voltage with the 8.5v plugs in place? It might help us diagnose the circuit. We can plug the voltages into a paralell-series circuit resitance calculator to paper-test possible schematics for any wiring problems.
Thinking this thread might have some grains of knowledge that could shed some light on this situation. I've been focusing on the portion of the circuit from the relay to the plugs. Could be something upstream of the glow plug relay has changed and is allowing more current to flow than the stock wiring setup.
that's to be expected. As the glow plugs heat up their resistance increases very quickly. When you first start the glow cycle the plugs could draw 60 to 75 amps depending on the brand of plug, the current will drop off quickly as the heat up. Id' expect somewhere around 35 to 50 amps depending on the glow plug. (I have been testing these things and collecting a lot of data.
Sorry guys - but this is one of "many" things that I am having a hard time understanding and it is not easier in a foreign language It is impressive with all you guys knowledge in this subject - wow!
Will you please do us a favor?
Take out the controller from the dash like in this picture
And do the following:
Take your voltmeter and connect the black lead to ground/body/bare metal.
Connect the red lead to the black/yellow wire
Turn the key and read the voltage...
Now do the same but connect the red lead to the black wire
Turn the key and read the voltage...
Just to prove that Toyota thinks we have all the right parts here:
(From my experience, 56021 and 56022 are likely to be the same because changing the last digit by 1 like this usually implies complete interchangeability.)
It kind of looks like those PT100 plugs are the culprit. We certainly can't rule that out. (But plugs are expensive in your region so I guess we're all trying to see if maybe something else is wrong before settling on the advice to try another brand/part-number.
I think the question here is: WHERE do those wires go?
If one of them is to ground you have an indicator light that shows that there is voltage on the busbar.
You have to check the wiring from the relay to the controller to the busbar.
I'm with Tom thinking that the/a PO rewired the system to get it going.
In my case, my BJ40 was re-wired to bypass the burned out controller and the PO put the full 12V on my (poor) 8.5V plugs. One was burned out, one was high ohms and the other two were barely alive.
Well .... I'm less sure of the incorrect wiring now. (I kind-of leapt at Jesper's statement that the controller was "just like another glow plug" because of course it shouldn't be wired up as "just another glow plug".
Just like mine does in my video? Well that looks quite normal then. (It should be heading for 8.5V at full glow.)
Nice to see both Rufus and Rudi involved now.... We must surely get somewhere eventually on this!
Edit: Looking at what Ozcruiser has posted and what Rudi and Rufus are saying ... the possibility of some sort of short-circuit existing downstream from the glow controller certainly needs to be eliminated before you look at buying more plugs.
Or maybe someone's tacked an extra cylinder (with extra glow plug) on the end to give extra load (and extra current-draw)
It is impressive with all you guys knowledge in this subject - wow!
