P0712

WITH 4L60-E AUTOMATIC TRANSMISSION

DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit:

Transmission Range (TR) Pressure Switch Assembly Wiring Assembly:

CIRCUIT DESCRIPTION
The Transmission Fluid Temperature (TFT) sensor is a thermistor within the Transmission Range (TR) pressure switch assembly that controls the signal voltage to the Vehicle Control Module-A (VCM-A). The VCM-A supplies a 5 volt reference signal to the sensor on CKT 1227. When the transmission fluid is cold, the sensor resistance is high and the VCM-A will sense high signal voltage.
As the transmission fluid temperature warms to the normal operating temperature of 100°C (212°F), the sensor resistance becomes less and the voltage decreases to 1.5 to 2.0 volts. With a DTC P1812 also set, check the transmission cooling system. DTC Type (D).

DTC P0712 WILL SET WHEN
Signal voltage indicates TFT less than 0.33 volts for one second.

ACTION TAKEN (VCM-A will default to)
When DTC P0712 is set, the transmission will use a defaulted value for operation, but the scan tool will display the actual transmission fluid temperature. The transmission will be in hot mode. DTC P0712 will be stored in the VCM-A memory and will turn "ON" the MIL (Malfunction Indicator Lamp) (if applicable).

DTC P0712 WILL CLEAR DEFAULT ACTION WHEN
The fault condition(s) no longer exist, and the ignition is cycled "OFF" for five seconds, then "ON".

DTC P0712 WILL PASS WHEN
- The VCM-A will report a "PASS" when transmission temperature drops below 146°C (295°F) for one second.
- The VCM-A turns "OFF" the Malfunction Indicator Lamp (MIL) after three consecutive ignition cycles with reported passes (if applicable).

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks for a short to ground or a skewed sensor.
2. This test checks for an internal fault within the transmission by creating an open.

DIAGNOSTIC AIDS
Check harness routing for a potential short to ground in CKT 1227. Scan tool TFT display should rise steadily to about 100°C (212°F) then stabilize.
Refer to Intermittents.
The temperature to resistance value scale may be used to test the TFT sensor at the various temperature levels to evaluate the possibility of a "skewed" sensor. A "skewed" (mis-scaled) sensor could result in delayed garage shifts or Torque Converter Clutch (TCC) complaints.
Verify customer driving habits, trailer towing, etc..