LRA Controller sorcery. (14 Viewers)
- Thread starter Fisher23
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Schrodinger's aux tank
Mine has had one of the middle green lights go off and on before but I’ve never experienced the Schrödinger error. I’d check for loose connections, try tapping the gauge first maybe.
- Thread starter
- #4
Has anyone seen this behavior?
Taping the gauge had no effect or rocking the vehicle to rock the sender.
Turning the vehicle on and off same display.
When turning on it goes through a check phase, beeps, then flashed red, green-light-1, green-2, green-3, green-light-4, yellow (individually) then beeps again does the red& green display.
When the lights flash they flash one at a time, nothing combined.
I don't remember this beeping when I started the vehicle before so that is new.
Maybe it needs to re-coded? or maybe it can't remember what was coded? or Maybe it just went bad and needs to be replaced.
There is a back door to code these, so you can turn on the automatic re-fueling, but Id' have to look it up and can't remember at the moment what the resistance settings were. (auto refueling is when your main tanks drops to 1/4 this automatically turns on and then turns off when either the main goes to 3/4 full or the aux gets the red empty light). This is controlled by the black and white wire.
Taping the gauge had no effect or rocking the vehicle to rock the sender.
Turning the vehicle on and off same display.
When turning on it goes through a check phase, beeps, then flashed red, green-light-1, green-2, green-3, green-light-4, yellow (individually) then beeps again does the red& green display.
When the lights flash they flash one at a time, nothing combined.
I don't remember this beeping when I started the vehicle before so that is new.
Maybe it needs to re-coded? or maybe it can't remember what was coded? or Maybe it just went bad and needs to be replaced.
There is a back door to code these, so you can turn on the automatic re-fueling, but Id' have to look it up and can't remember at the moment what the resistance settings were. (auto refueling is when your main tanks drops to 1/4 this automatically turns on and then turns off when either the main goes to 3/4 full or the aux gets the red empty light). This is controlled by the black and white wire.
Look here for clues! Seems like you are in test mode. I think you are getting too much resistance on sender line 1.
Thanks for posting this, I’ve been meaning to add it to the manuals I keep on my phone.
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- #7
Thanks !!
Looks like I have a bad ground on the black wire and it went into the test mode like you said. I'll check it on the weekend.
I do want to hook the white/black to the Main Fuel sender which should be one of the wires going into the consol.
Does anyone know which plug and pin number on the console is the fuel sender?
It would be nice to have it run automatically.
Looks like it needs 1 to 2 volts to turn on and 3 to 4 volts to turn off.
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I think this is a great idea. Please post if you figure out a way
Depending on how the light falls, mine can/does look more full than it is at times. I use mileage exclusively for fuel; don't trust gauges on either tank. Just me?
I sort of do the same. I don’t want to get too low and since I tow my mileage could be drastically off depending on the situation. I try to not let it get below half a tank on the main if I’ve exhausted the LRA.
My only issue is I can’t fill the LRA up all the way… that or I’m not getting it all out.
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- #12
My issue was a bad ground, so that is fixed.
For not getting the 39.7 gallons out:
When the red light turns on then after a set period of time the pump turns off.
After it turns red you can hit the button again and it will again pump for that set period of time and turn off.
On mine I can hit the button 3 times after it initially turns red to get the last few gallons out of it.
Mine I can hear the pump running and it makes a different sound if it is not pumping fuel.
So you may want to try that to get the reserve out of the aux tank?
For not getting the 39.7 gallons out:
When the red light turns on then after a set period of time the pump turns off.
After it turns red you can hit the button again and it will again pump for that set period of time and turn off.
On mine I can hit the button 3 times after it initially turns red to get the last few gallons out of it.
Mine I can hear the pump running and it makes a different sound if it is not pumping fuel.
So you may want to try that to get the reserve out of the aux tank?
The OEM gauge cluster expects a signal in ohm. It’s near zero ohm for one state and a high number (220? Ohm, have to look in the aux tank thread for the exact value) <edit 15 ohm full and 410 ohm empty> for the other state. The Toyota ohm range is not standard with a lot of aftermarket gauges / senders set up for 0 to 90 ohm.
It is possible to tap the gauge cluster wires and feed them the ohm value from the aux tank. I have mine on a switch, so I can read either one. For the OEM aux tank, it’s not super useful as the aux tank empties first due to the Venturi feed, which is automatic and not defeatable, so the fuel level of the aux tank is either being used or empty, during which time the main fuel tank garage reads full. When the main gauge is not on full, the aux tank is empty. I never have trouble with tracking about how much is my the aux tank because of this.
Another minor issue is that the fuel gauge doesn’t sample very often, so it could be a while from reading one tank value to the other after switching.
And finally, the gauge cluster inputs to the TLC and LX differ, so the wiring pins are different. Definitely follow the pin out / color codes for your year and model.
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I have done one extra pump but not anymore than that. We can’t hear it unless I’m stopped and 99% of the time we’re on the go so listening out for it is something I will also try. What does a empty pumping pump sound like?
I do hear the pump surge from time to time if I do come to a red light but it’s never been closed to empty… I have chalked this up to changes in idle speed with the AC on.
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- #15
Next time it goes red and you have parked and turned off the engine..
You could just hit the ignition button twice.. but don't start the vehicle, and try it then.
Without the engine running you can hear it easy.
Then you'll know how many times you can hit the refuel button while it's red.
At least that way you'll know how much reserve you have.
Then when you refuel you see how many gallons.
You could just hit the ignition button twice.. but don't start the vehicle, and try it then.
Without the engine running you can hear it easy.
Then you'll know how many times you can hit the refuel button while it's red.
At least that way you'll know how much reserve you have.
Then when you refuel you see how many gallons.
Thanks for the insights. I guess (at a minimum), I would need to try to integrate a device like this if I want automatic filling from the Aux to the main tank using the PG210: https://shop.classicinstruments.com/sn34 . Generics can be ordered for ~$35USD...not sure how well they might work. The juice might not be worth the squeeze.
The stock gauge is 15 ohm full and 410 ohm empty. I couldn’t find anything aftermarket that accommodated this range, but I also didn’t look exhaustively. A raspberry pi type solution or even simpler on one of those mini IC type things could easily do this, but I didn’t go down that path.
