Transmission Inputs

Transmission Range Sensor 

Due to transmission bulkhead connector issues the 4 bit digital TRS used by 6R80 with an internal TCM has been revised. The sensor now contains a micro processor that converts the 4 bit digital signal from into a Pulse Width Modulated (PWM) 125 Hz signal that is then output to the PCM. The sensor outputs a specific duty cycle for each bit pattern, including the invalid bit patterns. TRS is tested for invalid bit pattern (P0705 - inferred by the PCM thru the duty cycle), frequency out of range (P0706), duty cycle out of range low (P0707), duty cycle out of range high (P0708).

Speed Sensors 

The Turbine Shaft Speed (TSS) sensor and Output Shaft Speed (OSS) sensor are Hall effect sensors.

The Turbine Shaft Speed sensor is monitored for circuit faults and rationality (P0715, P0717). If turbine shaft speed exceeds a maximum calibrated speed (7, 700 rpm), a fault is stored (P0716). If engine speed and output shaft speed are high and a gear is engaged, it can be inferred that the vehicle is moving. If there is insufficient output from the TSS sensor a fault is stored (P0716).

The Output Shaft Speed sensor is monitored for circuit faults and rationality (P0720, P0722). If output shaft speed exceeds a maximum calibrated speed (7, 450 rpm), a fault is stored (P0721). If output shaft speed does not correlate with turbine shaft speed and wheel speed while a gear is engaged and the vehicle is moving, a fault is stored (P0721). If the output shaft speed decreases at an erratic/unreasonable rate, a fault is stored (P0723).

Transmission Fluid Temperature 

The Transmission Fluid Temperature Sensor is checked for open circuit, short circuit to ground, short circuit to power, and in-range failures (P0711, P0712, P0713, P0714). In-range TFT (P0711) is now the Ford standard diagnostic - the internal TCM temperature sensor is no longer available to diagnose TFT failures.