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Without Scan Tool

DIAGNOSTIC CODE INTERPRETATION

The Transmission Control Unit monitors operation of the transmission control system. Some components are monitored continuously, others only during specified operating conditions. When the TCU detects a malfunction lasting longer than a specified period of time the TCU will generate an error code that can be detected at the diagnostic connector.


If multiple malfunctions occur the diagnostic codes will be sent sequentially beginning with the lowest number code in ascending order with a 2 second pause between each code. A maximum of up to 10 fault codes can be stored in the control unit's memory and the same fault code can be stored as many as three times. If the number of stored codes exceeds 10, previously stored codes will be erased, beginning with the oldest code.

The voltmeter needle will deflect for a particular duration and a certain number of times.
FOR EXAMPLE:
Code 13
The needle will deflect one time for approximately 0.5 second. This will represent one unit of ten. There will be approximately a one second delay and then the needle will deflect three times for approximately 0.2 seconds with 0.1 second delay between deflections. This will represent three units of one.
Code 23
The needle will deflect two times for approximately 0.5 second with approximately 0.3 second delay between deflections. This will represent two units of ten. There will be approximately a one second delay and then the needle will deflect three times for approximately 0.2 seconds with 0.1 second delay between deflections. This will represent three units of one.


If the fail safe system is activated and the transaxle is locked in 3rd gear, a fault code from the fail safe code chart will be stored. Cancellation will occur if, with the transaxle locked in 3rd gear, the ignition key is turned to the OFF position, the code is stored until cleared.




Data Link Connector:






READING DIAGNOSTIC CODES

1. Connect an analog voltmeter to the ground and the transmission self diagnosis output pin of the diagnostic connector.

2. Set the ignition switch to "ON".

3. Note the pattern of pulses displayed on the voltmeter. If the voltmeter indicates a steady voltage (either 0 volts or 12 volts) the TCU has failed.

4. Refer to the diagnostic codes chart to determine which device is causing the malfunction code.

5. Test and repair the offending components as necessary.

6. Clear the malfunction codes by disconnecting the vehicle battery negative terminal for ten seconds or longer.

7. Road test the vehicle and recheck for newly stored diagnostic codes.

8. After the cause of a failure code has been detected and corrected the diagnostic code memory of the TCU should be cleared by disconnecting the vehicle battery for 10 seconds or more.