Powertrain Controls - ECM/PCM

Trouble Code 58 Chart:

Trans Fluid Temp Circuit Wiring Schematic:

CIRCUIT DESCRIPTION
The Transmission Fluid Temperature (TFT) sensor is a 2 wire thermistor located in the transaxle. This sensor operates in the same way as an Engine Coolant Temperature (ECT) or Intake Air Temperature (IAT) sensor. The Powertrain Control Module (PCM )applies 5 volts to the sensor on Circuit (CKT) 1227. The voltage sensed at PCM pin "A32" will be high when the trans fluid is cold, and as the trans fluid warms the voltage signal will drop. A very low signal voltage therefore indicates a high fluid temperature or a failure in the sensor circuit. Normal fluid temperatures range between 75°C (167°F) and 100°C (212°F).

DIAGNOSTIC TROUBLE CODE (DTC) 58 WILL SET WHEN
The TFT sensor indicates a temperature of 148°C or greater for 5 seconds.

ACTION TAKEN (PCM WILL DEFAULT TO)
The Malfunction Indicator Lamp (MIL) will become illuminated and the PCM will use a default TFT of 90°C.

DTC 58 WILL CLEAR WHEN
A current DTC 58 will clear when the TFT sensor temperature is indicated below the calibrated high temperature threshold. A History DTC 58 will clear after 50 consecutive ignition key cycles without a current DTC 58 being stored.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks if CKT 1227 is shorted to ground which will cause the conditions for DTC 58.

DIAGNOSTIC AIDS
^ Check harness routing for a potential short to ground in CKT 1227.
^ Scan tool displays transmission temperature in degrees centigrade. The temperature should rise steadily to about 85°C then stabilize.
^ A "skewed" sensor could result in delayed garage shifts or Torque Converter Clutch (TCC) enabled complaints.