Glow plug controller

[Batsford]

Hay Dave thanks for the paper ! I don't trust computers that others program, the screen could lie. Putting a light on the GP bus will CONFIRM it gets power and for how long. The 'idiot light' on the LCD screen is a 'should be' indicator. Wonder if the WSM has a chart for how long vs temperature the GPs will be on ?

I haven’t found much in the WSM regarding glow plugs or the engine…….but I can tell you anything you ever wanted to know about the A/C unit from it! Maybe there is a separate WSM for the engine.

 

[Batsford]

The excavator has a black and white LCD screen to communicate with the operator about GP , auxiliary hydraulics, no charging etc.

Dave

At this point he glow plug symbol only stays on for 6-8 seconds. I do need to check the voltage at the plugs again, but that’s a two man job and I haven’t asked my wife to come out to the cold garage and sit in the cold cab to turn the key……May have to wait till spring! Have you ever tried wiring the glow plugs directly with their own switch?

 

[GreensvilleJay]

I'm pretty sure <10 seconds is too little time, 'gut' thing. 'SHould ' be a chart in the owners manual.I use 5 seconds in a 50*F garage for my BX23S.
Test light could be a 1157 trailer unit on long wires attached to GP power rail and ground. That way light is 'in your face' while you sit in the freezing cold cab during testing and wifey's in the nice warm house, sitting in front of fireplace, drinking glass of wine..........

 

[Batsford]

I'm pretty sure <10 seconds is too little time, 'gut' thing. 'SHould ' be a chart in the owners manual.I use 5 seconds in a 50*F garage for my BX23S.
Test light could be a 1157 trailer unit on long wires attached to GP power rail and ground. That way light is 'in your face' while you sit in the freezing cold cab during testing and wifey's in the nice warm house, sitting in front of fireplace, drinking glass of wine..........

I thought of running a long wire from the gp rail to a multi-tester in the cab, but in the excavator things are so tight I can’t reach in there to attach a clip to the rail! Hence the need for my wife, (I can reach it with the probe) I’m guessing the rail in my bx25 is right out in the open like your bx23….fireplace and wine to warm up afterwards.

 

[Batsford]

I thought of running a long wire from the gp rail to a multi-tester in the cab, but in the excavator things are so tight I can’t reach in there to attach a clip to the rail! Hence the need for my wife, (I can reach it with the probe) I’m guessing the rail in my bx25 is right out in the open like your bx23….fireplace and wine to warm up afterwards.

Also I’’ll double check the owners manual

 

[Dave_eng]

At this point he glow plug symbol only stays on for 6-8 seconds. I do need to check the voltage at the plugs again, but that’s a two man job and I haven’t asked my wife to come out to the cold garage and sit in the cold cab to turn the key……May have to wait till spring! Have you ever tried wiring the glow plugs directly with their own switch?

If you start powering GP's with direct 12 volts you risk them overheating and exploding leaving shards of ceramic in the cylinder.
Have you tried the method I have suggested?
Dave

 

[Batsford]

Since you've replaced all the plugs, have good voltage and the machine runs, so unlikely the ECU.
Hopefully the WSM has the specs for that water sensor, how to test and maybe what temperature the ECU looks at to control the glow plugs, and HOW the ECU actually controls the power to glowplugs.
If, say the ECU reads the sensor as 'warm' when it's actually 'cold', then the ECU probably won't heat the glow plugs as much and that could cause 'hard starting'. Maybe check the wiring from sensor to ECU.
Most electrical problems are a series of 'test and eliminate, next' but you need the WSM/ wiring diagram, and you've got that. Check WSM for a 'trouble shooting check list' ?

The WSM tells me every thing I ever wanted to know about the A/C but very little on the engine……it did give guidance on getting into the “testing” screens which do show the water temp and 100 other things…nothing specific to glow plugs..and no trouble shooting for the engine! I’m trying to get a WSM for the engine. The wiring diagram shows wires from the glow plug rely going into the ECU . I guess the next step will be studying those testing screens some more to see if everything they do show is in spec.

 

[Batsford]

If you start powering GP's with direct 12 volts you risk them overheating and exploding leaving shards of ceramic in the cylinder.
Have you tried the method I have suggested?
Dave

Thanks. I did try cycling the switch on and off multiple times to no avail.. with it -11F here this morning guess I’ll hold off today before re-checking voltage to the glow plugs and studying the ECU screen in “testing”mode more throughly to see if anything show up out of spec. Thanks for the heads up on direct wiring the glow plugs.

 

[GreensvilleJay]

Honestly, I know this is painful...but make the test light unit.
Wire an alligator clip onto a LONG single wire, attach onto the GP busbar.
connect the 'free end (now in the cab with you' to the +ve to your meter with -ve clipped to ground.
I prefer using an 1157 taillight as it's EASY to see,while you turn the key and stuff.
After you're done testing, you can yank on the wire and ally comes off easy !
This is the only test I know that CONFIRMS power is getting to the GPs. The dash 'computer' it 'should' be on,but unless it has 'feedback' it doesn't actually know.
At -11, I'd think GPs need 1-2 minutes of heat ? The 'manual' should have a chart ?

 

[Batsford]

Honestly, I know this is painful...but make the test light unit.
Wire an alligator clip onto a LONG single wire, attach onto the GP busbar.
connect the 'free end (now in the cab with you' to the +ve to your meter with -ve clipped to ground.
I prefer using an 1157 taillight as it's EASY to see,while you turn the key and stuff.
After you're done testing, you can yank on the wire and ally comes off easy !
This is the only test I know that CONFIRMS power is getting to the GPs. The dash 'computer' it 'should' be on,but unless it has 'feedback' it doesn't actually know.
At -11, I'd think GPs need 1-2 minutes of heat ? The 'manual' should have a chart ?

Thanks again. I tried an alligator clip to both ends of a long wire. The challenge is that I don’t have any Japanese friends with small enough hands and arms to reach around the common rail to attach an end to the GP busbar……I’m,starting to think the excavator was designed in Germany! It’s supposed to warm up a bit this week so with a friend I should be able to verify power to the GP’s and the voltage ( some where I read they only want 11.5 volts) but I’m going to research that again too). I did down load a WSM for the excavator and an operator/owner manual for the engine but neither one gives any info on the glow plugs. On another note the owner/operator for the excavator lists engine oil capacity at 1.32 gal. And the engine manual lists 1.85 g….amazing!

 

[Batsford]

Thanks again. I tried an alligator clip to both ends of a long wire. The challenge is that I don’t have any Japanese friends with small enough hands and arms to reach around the common rail to attach an end to the GP busbar……I’m,starting to think the excavator was designed in Germany! It’s supposed to warm up a bit this week so with a friend I should be able to verify power to the GP’s and the voltage ( some where I read they only want 11.5 volts) but I’m going to research that again too). I did down load a WSM for the excavator and an operator/owner manual for the engine but neither one gives any info on the glow plugs. On another note the owner/operator for the excavator lists engine oil capacity at 1.32 gal. And the engine manual lists 1.85 g….amazing!

For the heck of it I just braved the cold to check the location of the GP’s on my bx25……right along the top, easy to get to, test or replace….like I said maybe the D1803 engine was designed in Germany !

 

[GreensvilleJay]

Thanks for the giggle ! I have a great grandson whose hands are juuust the right size !!! maybe the designer's the same guy who put the starter for an engine INSIDE of it ??
My fun day...decide to put rollup toneau cover back down on truck. needs to go into garage.remote doesn't start it,battery low, need to pop hood, can't, both doors frozen shut. When I finally get it into warm garage(BX23S not happy outside....) ALL my spare batteries are 'wrong way round' top posters.Hopefully cleaning everything and bench charging is all I need cause, yup, snowing again.BTW the ice on my sloped driveway is really,really, really sliiiiiiipppppery.

 

[Batsford]

Thanks for the giggle ! I have a great grandson whose hands are juuust the right size !!! maybe the designer's the same guy who put the starter for an engine INSIDE of it ??
My fun day...decide to put rollup toneau cover back down on truck. needs to go into garage.remote doesn't start it,battery low, need to pop hood, can't, both doors frozen shut. When I finally get it into warm garage(BX23S not happy outside....) ALL my spare batteries are 'wrong way round' top posters.Hopefully cleaning everything and bench charging is all I need cause, yup, snowing again.BTW the ice on my sloped driveway is really,really, really sliiiiiiipppppery.

Figure it’s a good day if we can laugh about it!

 

[GreensvilleJay]

and NO bandaids ! I have OMS and it's a 'challenge'.

 

[Batsford]

and NO bandaids ! I have OMS and it's a 'challenge'.

And no bruises on the back of the hands(that happens to this old guy a lot)!