Microtech LT8 Multiple sensor errors & incorrect voltage reading
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LT8 Multiple sensor errors & incorrect voltage reading
I just wired up my LT-8 that I got, and I am getting errors for the air temp sensor, water temp sensor, MAP sensor, and the TPS is reading 99% all the time. I also notice that it is saying my voltage is 15.95V, with the engine not running. I have not started the engine yet.
If I unplug all of the sensors, I still get errors for the air temp and water temp, TPS still reads 99%, but map sensor says OK. This has an external MAP sensor and with the MAP sensor plugged in, I am reading 30PSI boost, with it unplugged, it reads full vacuum, even tried a different MAP sensor (uses GM MAP). If I try to set the TPS, it reads 99% all of the time, even when the TPS is pushed in all the way. I dont know why it is showing 15.95V, because the voltage at the power wire on the unit is 12.3V. I checked all of my wiring, and it all appears to be good, have zero resistance to ground where it should be grounded, full battery voltage on all of the power wires, I did splice into the harness at the ECM connectors, cut and soldered all wires, used heat shrink to seal, and I unplugged all unused sensors (AFM, stock MAP & ATP, variable resistor, BAC). The fuel pump primes when the ignition is first turned on, and measuring voltage at the sensors with errors, I am getting 5.02V to each sensor.
Hopefully its something simple that I missed, and not a bad ECU. Anybody have any ideas?
I have attached a screenshot of the ECU readings, ignition on, engine off. I can give a list of wires I tapped into if needed.
If I unplug all of the sensors, I still get errors for the air temp and water temp, TPS still reads 99%, but map sensor says OK. This has an external MAP sensor and with the MAP sensor plugged in, I am reading 30PSI boost, with it unplugged, it reads full vacuum, even tried a different MAP sensor (uses GM MAP). If I try to set the TPS, it reads 99% all of the time, even when the TPS is pushed in all the way. I dont know why it is showing 15.95V, because the voltage at the power wire on the unit is 12.3V. I checked all of my wiring, and it all appears to be good, have zero resistance to ground where it should be grounded, full battery voltage on all of the power wires, I did splice into the harness at the ECM connectors, cut and soldered all wires, used heat shrink to seal, and I unplugged all unused sensors (AFM, stock MAP & ATP, variable resistor, BAC). The fuel pump primes when the ignition is first turned on, and measuring voltage at the sensors with errors, I am getting 5.02V to each sensor.
Hopefully its something simple that I missed, and not a bad ECU. Anybody have any ideas?
I have attached a screenshot of the ECU readings, ignition on, engine off. I can give a list of wires I tapped into if needed.
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I am going to conclude that this thing is a pile of garbage. The only thing that seems to work on it is the fuel pump prime, and the laptop connector, it reads maps just fine, but all of the inputs are dead. The oddest one is voltage being incorrect? Doubt I will keep with Microtech, I heard good reviews about them, and since I got one, all I have been able to find are limitations. Going to look into buying a new ECM now.
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I am going to conclude that this thing is a pile of garbage. The only thing that seems to work on it is the fuel pump prime, and the laptop connector, it reads maps just fine, but all of the inputs are dead. The oddest one is voltage being incorrect? Doubt I will keep with Microtech, I heard good reviews about them, and since I got one, all I have been able to find are limitations. Going to look into buying a new ECM now.
Do you have the handset or dash? Does it read the same as the software?
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I have a handset that came with it, it shows the same as the laptop. I powered it up with only the power and grounds, same errors for water and air temp sensord, 99% tps, 30mm hg, 15.95v.
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