DTC 80

DTC 80 Transmission Component Error:

Transmission Harness Schematic:

CIRCUIT DESCRIPTION
The Torque Converter Clutch (TCC) is monitored for slip by calculating the difference between engine speed and transaxle output shaft speed Vehicle Speed Sensor (VSS). When the TCC is engaged, a nominal amount of slippage will be acceptable and is caused by small calculation errors. A slippage of 10 to 25 RPM is not uncommonly seen using a scan tool when TCC is engaged.

DIAGNOSTIC TROUBLE CODE (DTC) 80 WILL SET WHEN
Gear selector in 3rd or 4th gear, engine running, TCC is commanded "ON," throttle angle is between 1% and 74%, Transmission Fluid Temperature (TFT) is between 40° C (104° F) and 80° C (176° F) and more than 150 RPM slippage is detected for 8 seconds.

POWERTRAIN CONTROL MODULE (PCM) WILL DEFAULT TO
TCC and 4th gear will become disengaged. "D1," "D2" and "D3" will continue to be selected. The Malfunction Indicator Lamp (MIL) will not become illuminated.

DTC 80 WILL CLEAR WHEN
A current DTC 80 will clear after each ignition cycle. A History DTC 8O will clear after 50 consecutive ignition key cycles without a current DTC 8O being stored.

TEST DESCRIPTION
Numbers below refer to circled numbers on the diagnostic chart.

1. This test checks for circuit continuity of the TCC apply solenoid.
2. This checks for an open in the power feed circuit 439.
3. This test checks the Pulse Width Modulated (PWM) return circuitry to the PCM.

DIAGNOSTIC AIDS
The Tech 1 only indicates when the PCM has commanded the TCC driver "ON"; this does not confirm that the TCC is actually engaged. Check the 10 amp "ERLS" fuse. If open, a potential short could exist anywhere in circuit 439. This circuit serves many other components. To determine if TCC is functioning properly, road test the vehicle. Engine RPM should decrease when the Tech 1 indicates the TCC has been turned "ON." If diagnosis indicates that all electrical circuits and components are OK, refer to Automatic Transaxle / Testing and Inspection for hydraulic and mechanical diagnosis.