DTC 74

Diagnostic Chart:

Circuit Schematic:

3RD GEAR ACTUATOR CIRCUIT SHORTED TO VOLTAGE
3rd clutch is applied when circuit 1223 is opened at the PCM. When the PCM grounds the circuit the voltage is monitored at terminal J3F3 to check for proper circuit conditions.

INFORMATION FLAG PARAMETERS
Information flag 74 is set when the PCM has detected the following condition twice per ignition cycle.
- Voltage monitored at terminal J3F3 - (circuit 1223) is greater than 2- 2.5 volts, when the 3rd gear actuator is switched on electrically by the PCM.

TEST DESCRIPTION
Numbered steps below refer to numbered steps on chart.
1. This step verifies problem is still present.
2. If actuator, connector plate, or circuit 1223 is shorted, information flag 74 will set. This step will break the circuit down to find the source of the short.
3. If circuit 1223 is shorted to voltage, information flag 74 will set. This step checks circuit 1223 for a short to voltage.
4. This step will determine if it is the actuator or the actuator connector plate that is shorted. An actuator is shorted internally when its resistance is one or more ohms lower than the average resistance of the other actuators at the same temperature.

DIAGNOSTIC AIDS
When attempting to diagnose an intermittent problem use the Scan tool[1] to review supplemental diagnostic information. The supplemental data can be used to duplicate a problem.

Check the tightness of the female terminal grip with a spare male terminal.

When the PCM detects a fault in the circuit (open, ground, short) the PCM will open the circuit internally to protect the circuit.
- Conditions that set this information flag will probably result in a DTC 75 - 3rd Gear Stuck On and a DTC 25 - No TCC.

[1] Select Malfunction History from Scan tool Transaxle Controller (TC) menu.