IC damaged?

Jj Technician Massachusetts Posted   Latest  
2006 Dodge Ram 1500 SLT 4.7L (N) 5-spd (545RFE)
P0463 — Fuel Level Sensor "A" Circuit High

Long story short, fuel sender signal is shorted to pump voltage. When I split the signal circuit the sender side voltage "primes" when the pump primes, but it's always a couple volts less than battery voltage. Where it's shorted is TBD. All service info I can find says it should be a 5v signal from the IC for the fuel sender. With the circuit split I have about 11v coming from the IC. Did the short take out the voltage regulator in the cluster or is service info incorrect?

Stephen Technician
Stephen Default

DTC463 trouble tree says to read the sensor voltage on the scan tool, with the ckt connected. I would connect a 150ohm(there abouts) resistor, from ground, to the IC side of the isolated N4 ckt. Cycle key, check gauge reading and voltage at the resistor.

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Jj Technician
Jj Default

Gauge reads just over quarter tank, 4.9v at the resistor. For some reason sender voltage is nowhere to be found in scan data, just level. Edit:. Cluster appears to be fine. Identifix has a different operation description from Alldata. Using a variable resistor to change the voltage from the IC to match Identifix's info proves out the cluster. Also code does not reset until you send the…

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Ward Technician
Ward Default

Hello Jj! Years back I had a Dodge Caravan that had a fuel gauge issue - if memory serves it read reasonably accurately on the top half of the tank but the gauge would only go to / tank and then just stay there until the vehicle ran outta fuel (I think). Wr eventually traced it down to the plastic feed through in the floor where the harness went from inside the vehicle to underneath. Some how…

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