Any Ideas What’s Going On With My Dashboard Lights??

[jplace1011]

I’ve noticed that when I start my CUCV M1009 up the lights are dim and flicker. The Voltmeter is in the Yellow. The Water in Fuel Light will flash and then the lights and Voltmeter are normal. The interesting thing is the aftermarket Oil Pressure Light seems good all the time. Video from today below:

The other day the Water in Fuel Light was at a constant flickering too. It doesn’t seem to be doing that any longer. I just want to mention it. Video below from yesterday:

I recently did a lot of work to the dashboard: replaced the circuit behind the instrument bezel, installed LED bulbs, painted the gauge needles, etc.

When the Water in Fuel Light was constantly flickering I double checked the Big Plug at the rear of the instrument panel. I disconnected it and plugged it back in. That seemed to help and stopped the constant flickering. Still, now it’s doing this Flash and suddenly power is normal thing.

If it matters, I also replaced the both alternators, the temperature sensor, the glow plug card and relay late last year.

I’m not sure what exactly is going on. Is it the truck just needing a short time to get back up to the proper volts once the alternators kick in? Could it be the Fuel Sensor in the fuel filter needing replaced? I checked the wires for that sensor and they seem in good shape.

You guys have been so helpful. I appreciate any input with this! Thank you thank you!

-JP


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[dougco1]

I’ve noticed that when I start my CUCV M1009 up the lights are dim and flicker. The Voltmeter is in the Yellow. The Water in Fuel Light will flash and then the lights and Voltmeter are normal. The interesting thing is the aftermarket Oil Pressure Light seems good all the time. Video from today below:

The other day the Water in Fuel Light was at a constant flickering too. It doesn’t seem to be doing that any longer. I just want to mention it. Video below from yesterday:

I recently did a lot of work to the dashboard: replaced the circuit behind the instrument bezel, installed LED bulbs, painted the gauge needles, etc.

When the Water in Fuel Light was constantly flickering I double checked the Big Plug at the rear of the instrument panel. I disconnected it and plugged it back in. That seemed to help and stopped the constant flickering. Still, now it’s doing this Flash and power is normal thing.

If it matters, I also replaced the glow plug card and relay late last year.

I’m not sure what exactly is going on. Is it the truck just needing a short time to get back up to the proper colts once the alternators kick in? Could it be the Fuel Sensor in the fuel filter needing replaced? I checked the lines for that sensor and they seem in good shape.

You guys have been so helpful. I appreciate any input with this! Thank you thank you!

-JP


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It looks like you are getting a heavy electrical draw on your charging system. The volt gage should move into the green shortly after starting and pulse back and forth as the glow plugs cycle. It's possibly a problem with the glow plug system. The engine temperature sensor may be bad and is keeping your glow plugs activated or the glow plug card went bad again. Does it do it when the engine is warm?

After reading your post again, you said you replaced your dash bulbs with LEDs. Did you replace the gen 1 bulb? That incandescent bulb is needed as part of the generator exciter circuit and your alternator may not be charging properly.

 

[jplace1011]

It looks like you are getting a heavy electrical draw on your charging system. The volt gage should move into the green shortly after starting and pulse back and forth as the glow plugs cycle. It's possibly a problem with the glow plug system. The engine temperature sensor may be bad and is keeping your glow plugs activated or the glow plug card went bad again. Does it do it when the engine is warm?

After reading your post again, you said you replaced your dash bulbs with LEDs. Did you replace the gen 1 bulb? That incandescent bulb is needed as part of the generator exciter circuit and your alternator may not be charging properly.

Thanks for responding. I did indeed replace the Engine Temperature Sensor when I replaced the Glow Plug Card & Glow Plug Relay. I’m going to double check the Card, make sure it isn’t loose.

When I switched to LEDs, I kept the original type of bulbs in Gen. 1 & Gen. 2. I only knew of that prior, thanks to a video by @Rocknus.

I’m going to drive it today, I’ll see if it does it while warm. Good question indeed.

Thank you for the input. I’m hoping to get this figured out.


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[jplace1011]

Thanks for responding. I did indeed replace the Engine Temperature Sensor when I replaced the Glow Plug Card & Glow Plug Relay. I’m going to double check the Card, make sure it isn’t loose.

When I switched to LEDs, I kept the original type of bulbs in Gen. 1 & Gen. 2. I only knew of that prior, thanks to a video by @Rocknus.

I’m going to drive it today, I’ll see if it does it while warm. Good question indeed.

Thank you for the input. I’m hoping to get this figured out.


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I ended up replacing the Engine Temperature Sensor and Plug on-top.

The wiring on Old the plug was in bad shape.

Even after driving and warming up the vehicle, the power jump still happened.

The Glow Plug Card seems good, it wasn’t loose, etc. After all that, the power jump is still occurring.

I checked out the plugs on both alternators as well. Both were filthy, one in particular. That opened up a new problem, You can read about that here:

Gen 2 Light Stays On While Engine is Running
https://r.tapatalk.com/shareLink/to...-Running.208207/&share_type=t&link_source=app

The Gen 2 light now stays on while the engine is running.

I just can’t get this finished!


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[jplace1011]

I ended up replacing the Engine Temperature Sensor and Plug on-top.

The wiring on Old the plug was in bad shape.

Even after driving and warming up the vehicle, the power jump still happened.

The Glow Plug Card seems good, it wasn’t loose, etc. After all that, the power jump is still occurring.

I checked out the plugs on both alternators as well. Both were filthy, one in particular. That opened up a new problem, You can read about that here:

Gen 2 Light Stays On While Engine is Running
https://r.tapatalk.com/shareLink/to...-Running.208207/&share_type=t&link_source=app

The Gen 2 light now stays on while the engine is running.

I just can’t get this finished!


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I went ahead and fixed alternator 2 (I shorted it by accident) and I replaced the Relays for the Voltmeter & Gen 2. I disconnected the Ground Wire from the CB Radio as well. I discovered the previous owner wired it to a Hot Wire. I did this in case it’s drawing power when the vehicle is parked. I’ll fix that later.

Interestingly enough the Water in Fuel Light doesn’t buzz anymore, but it still flashes (the dash lights are still dimming) and the power returns to normal afterwards. Things are better, but not fixed. Quick Video below:

I wonder if the Water in Fuel Sensor could be bad or even the Low Coolant Module might be bad since the Water in Fuel Light is within that circuit. If one of those is bad, could they be drawing power? I may be way off.

Any ideas?


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[dougco1]

I went ahead and fixed alternator 2 (I shorted it by accident) and I replaced the Relays for the Voltmeter & Gen 2. I disconnected the Ground Wire from the CB Radio as well. I discovered the previous owner wired it to a Hot Wire. I did this in case it’s drawing power when the vehicle is parked. I’ll fix that later.

Interestingly enough the Water in Fuel Light doesn’t buzz anymore, but it still flashes (the dash lights are still dimming) and the power returns to normal afterwards. Things are better, but not fixed. Quick Video below:

I wonder if the Water in Fuel Sensor could be bad or even the Low Coolant Module might be bad since the Water in Fuel Light is within that circuit. If one of those is bad, could they be drawing power? I may be way off.

Any ideas?


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The water in fuel circuit would not draw that much power and should have no effect.
You are still getting a huge electrical draw "most likely" from your glow plug system. In your video, that rattle noise and then the back to normal acts as if your glow plugs are still heating in till the system "resets" itself.
Your new temp sensor may still be bad or wired wrong and not talking to your card. Or possibly your card is bad and is confused as to what its supposed to do.
Does your "wait to start" light function like it should? It should come on and stay on for a short time till the plugs heat up. Then your volt meter should pulse from yellow to green for a while till the engine warms up.
Have you inspected your card for burnouts? Try testing your card with a loner or buy a new card? Test the new temp sensor?

I know I already mentioned most of this in post #2 and I cant be certain from 3,000 miles away but my bet is a bad sensor.

 

[jplace1011]

The water in fuel circuit would not draw that much power and should have no effect.
You are still getting a huge electrical draw "most likely" from your glow plug system. In your video, that rattle noise and then the back to normal acts as if your glow plugs are still heating in till the system "resets" itself.
Your new temp sensor may still be bad or wired wrong and not talking to your card. Or possibly your card is bad and is confused as to what its supposed to do.
Does your "wait to start" light function like it should? It should come on and stay on for a short time till the plugs heat up. Then your volt meter should pulse from yellow to green for a while till the engine warms up.
Have you inspected your card for burnouts? Try testing your card with a loner or buy a new card? Test the new temp sensor?

I know I already mentioned most of this in post #2 and I cant be certain from 3,000 miles away but my bet is a bad sensor.

The Wait Light is functioning normally.

You have me thinking. I do have my old card, I’ll try switching it out and see if anything changes.

I’ll report back soon. Thank you for the advice, I appreciate it.


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[jplace1011]

The Wait Light is functioning normally.

You have me thinking. I do have my old card, I’ll try switching it out and see if anything changes.

I’ll report back soon. Thank you for the advice, I appreciate it.


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@dougco1 I switched the glow plug cards out. Still the same thing. I was thinking about it all. It did all of this before and after I replaced the Temperature Sensor. Maybe it’s the Glow Plug Relay? I replaced it last year though.

As far as the New Temp Sensor, is there a way to Test it? More specifically, how do I test the Plug & Wires for the Sensor??

I switched out the Low Coolant Module and started it after driving it for some time. The Water in Fuel Light does flash once very quickly right after start up. After the Flash, the Voltmeter does go into the Green quickly. I’m guessing that’s because the Glow Plugs are already warm?

I re-tested it again tonight and sure enough the light flashes again. I’m stumped!! Any ideas?!

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[jplace1011]

@dougco1 I switched the glow plug cards out. Still the same thing. I was thinking about it all. It did all of this before and after I replaced the Temperature Sensor. Maybe it’s the Glow Plug Relay? I replaced it last year though.

As far as the New Temp Sensor, is there a way to Test it? More specifically, how do I test the Plug & Wires for the Sensor??

I switched out the Low Coolant Module and started it after driving it for some time. The Water in Fuel Light does flash once very quickly right after start up. After the Flash, the Voltmeter does go into the Green quickly. I’m guessing that’s because the Glow Plugs are already warm?

I re-tested it again tonight and sure enough the light flashes again. I’m stumped!! Any ideas?!

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Interesting things I discovered. I unplugged the High Idle Switch and there was still a power draw after start up. The same thing happened when I unplugged the Water in Fuel Sensor.

Now I’m wondering if it could be the Ignition Switch, or the Glow Plug Relay. I’ll check those next.

I may have to test things for a power draw. Not sure how to though??


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[antennaclimber]

Your second video shows normal GP operation. What you discovered is more commonly known as after glow.
The GP's stay on after starting the engine for a little while until the GP card turns them off.

 

[dougco1]

Interesting things I discovered. I unplugged the High Idle Switch and there was still a power draw after start up. The same thing happened when I unplugged the Water in Fuel Sensor.

Now I’m wondering if it could be the Ignition Switch, or the Glow Plug Relay. I’ll check those next.

I may have to test things for a power draw. Not sure how to though??


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You have me thinking again. I think the temp sensor is a normally an open circuit "when cold". When the water temperature rises after starting or when it has already been running, the sensor loop closes and that tells your glow plug card that the engine is warm and doesn't need the glow plug system any longer. I also could have that all reversed. The sensor "cold" can be a closed circuit and "warm" would be an open circuit.

To check operation I would use a volt meter on the sensor contacts when its cold to see if you have continuity or not. Then check it again when its warm to see if you get different results. If you get the same results you have a non functioning temperature sensor.

If the sensor checks out as good I would start looking at the possibility of a faulty card again.

 

[antennaclimber]

The temp sensor for the glow plug card is a thermistor. It changes resistance with temperature change. This resistance value is used to calculate the time that the glow plug relay is closed.

The high idle sensor is a switch. It is either open or closed.

 

[jplace1011]

The temp sensor for the glow plug card is a thermistor. It changes resistance with temperature change. This resistance value is used to calculate the time that the glow plug relay is closed.

The high idle sensor is a switch. It is either open or closed.

Stupid question, I’m still learning: the Water in Fuel light Flashes right before the power goes up into the Green on the Voltmeter. That’s not normal right, the flashing?

Afterglow, that’s an interesting thing to learn, makes sense. I’ve thought maybe it (Voltmeter) should go up to normal sooner, but maybe that’s just because it takes a little time for the temp to get up high enough until it turns off.

I’ll have to test the Temp Sensor with my Voltmeter, as well as unplug it all together and look for the Water in Fuel Light flashing or not.


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[antennaclimber]

I'm not sure why the water/fuel light is flashing. I think you may have a ground connection that needs some attention. The CUCV is well know for poor grounds and poor electrical connections over time.

But the low voltage and dim lights until the GP relays opens is normal.
They are drawing nearly 100 amps when heating up. So a lower than normal voltage can be expected.

On my trucks, after they start, I usually rev the engine up slightly to bring up the system voltage during the after glow period. Not a full blown rev the crap out of it, just a little higher than normal.

 

[jplace1011]

I'm not sure why the water/fuel light is flashing. I think you may have a ground connection that needs some attention. The CUCV is well know for poor grounds and poor electrical connections over time.

But the low voltage and dim lights until the GP relays opens is normal.
They are drawing nearly 100 amps when heating up. So a lower than normal voltage can be expected.

On my trucks, after they start, I usually rev the engine up slightly to bring up the system voltage during the after glow period. Not a full blown rev the crap out of it, just a little higher than normal.

I’ll take a look at the charts and see if I can find the grounds for the circuits the Water in Fuel Light is on. Then I’ll check the Ground wires I find. I’ve already had to repair a few, what’s another one to have to fix right?

I’m happy to hear that the dimming lights is normal. I just wasn’t sure. Wow the Relay pulls some juice huh?

I’ll have to report back about what/if I find anything in regards to that Flashing Light and Ground(s) for it.

Thank you for the input, I’m learning every day!


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[jplace1011]

I’ll take a look at the charts and see if I can find the grounds for the circuits the Water in Fuel Light is on. Then I’ll check the Ground wires I find. I’ve already had to repair a few, what’s another one to have to fix right?

I’m happy to hear that the dimming lights is normal. I just wasn’t sure. Wow the Relay pulls some juice huh?

I’ll have to report back about what/if I find anything in regards to that Flashing Light and Ground(s) for it.

Thank you for the input, I’m learning every day!


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Just as a test, I disconnected the Temperature Sensor as well as the Fuel Heater plug (that’s one thing I repaired the wires for earlier on). I wanted to see if the Water in Fuel light would still flash if these two items were unplugged.

I also wanted to see what would happen with the Glow Plug Card in relation to the Water in Fuel light flashing.

I started it up, soon after as the Red Light in the Glow Plug Card Flashed Off the the Water in Fuel Light Flashed On and the Voltmeter returned to Normal.

Video here, sorry it drags on a bit:

I think you’re right in saying that’s what’s drawing the power. This says it can take up to 90 seconds for the After Glow Period to end.

Now it doesn’t explain the Water in Fuel light flashing, but we already discussed checking the grounds. Is there a simple way to check the grounds with a Multimeter, Power Probe, etc.? Maybe that’s a Continuity Test, not that I know how to perform one?


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[dougco1]

Just as a test, I disconnected the Temperature Sensor as well as the Fuel Heater plug (that’s one thing I repaired the wires for earlier on). I wanted to see if the Water in Fuel light would still flash if these two items were unplugged.

I also wanted to see what would happen with the Glow Plug Card in relation to the Water in Fuel light flashing.

I started it up, soon after as the Red Light in the Glow Plug Card Flashed Off the the Water in Fuel Light Flashed On and the Voltmeter returned to Normal.

Video here, sorry it drags on a bit:

I think you’re right in saying that’s what’s drawing the power. This says it can take up to 90 seconds for the After Glow Period to end.

Now it doesn’t explain the Water in Fuel light flashing, but we already discussed checking the grounds. Is there a simple way to check the grounds with a Multimeter, Power Probe, etc.? Maybe that’s a Continuity Test, not that I know how to perform one?


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I still think you may have a bad card, temp sensor, or both.

The video shows on "your volt meter" that the GPs were/are fully activated when you started the truck "I assume when the engine was already warm". Also the GPs after glow never worked properly in any of your videos. The after glow should pulse the GPs on and off after a cold start like it says in the TM. That will show up on your volt meter needle pulsing back and forth from green to yellow as it cycles. None of your videos show the meter pulsing like that.

I think your GPs come on and stay on steady with "no cycling after glow" in till it kicks off. That tells me its a bad card, temp sensor, or possibly a wiring problem.

 

[jplace1011]

I still think you may have a bad card, temp sensor, or both.

The video shows on "your volt meter" that the GPs were/are fully activated when you started the truck "I assume when the engine was already warm". Also the GPs after glow never worked properly in any of your videos. The after glow should pulse the GPs on and off after a cold start like it says in the TM. That will show up on your volt meter needle pulsing back and forth from green to yellow as it cycles. None of your videos show the meter pulsing like that.

I think your GPs come on and stay on steady with "no cycling after glow" in till it kicks off. That tells me its a bad card, temp sensor, or possibly a wiring problem.

Hello Again
When I started the engine in that video, it was cold. You’re right about the Voltmeter not pulsating.

I realized I never checked the temp sensor with a multimeter. I will do that next, it won’t hurt.

I’ll report back, thank you for the input. I need the help and appreciate it.


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[jplace1011]

Hello Again
When I started the engine in that video, it was cold. You’re right about the Voltmeter not pulsating.

I realized I never checked the temp sensor with a multimeter. I will do that next, it won’t hurt.

I’ll report back, thank you for the input. I need the help and appreciate it.


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@dougco1 Would I just test the sensor using a Continuity Test? Put the black probe end of the multimeter into the negative part of the plug (on the sensor) and touch any part of the positive probe (grounding it) on the engine? And do that to the other end, the end that plugs into the top of the sensor? If I hear an audio tone/beep that means there’s a good ground.

I may be way off?!

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[WWRD99]

@dougco1 Would I just test the sensor using a Continuity Test? Put the black probe end of the multimeter into the negative part of the plug (on the sensor) and touch any part of the positive probe (grounding it) on the engine? And do that to the other end, the end that plugs into the top of the sensor? If I hear an audio tone/beep that means there’s a good ground.

I may be way off?!

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That sensor is a basic resistor with a temp variant...so depending on temp it has a set amount of resistance...I am not sure what it should be so that is the unknown part...does the plug have power or is it a ground type? To test the sensor you need a lead on each of the pins in it...ohms read...any chance the wires are swapped on the new plug?