Cruise Control: Testing and Inspection

Self-Diagnostic Function
The self-diagnostic function integrated within the cruise control unit diagnoses the condition of the cruise control system.

Condition/operation codes, stored in the cruise control memory, are indicated by the cruise indicator in the instrument cluster. (Refer to condition code numbers below). Stored codes are deleted when the ignition switch is turned to OFF. In addition, the memory will hold only a single code at any time: If multiple malfunctions are present, the first one displayed will have to be corrected before the next code can be displayed.




1. Code cycle break. The time between condition code cycles is 4.0 seconds(the time the cruise indicator is off).




2. Second digit of code (ones position). The digit in the ones position of the code is determined by the number of times the lamp is on for 0.4 second (during one cycle).




3. first digit of code (tens position). The digit in the tens position of the code is determined by the number of times the lamp is on for 1.2 seconds(during one cycle). The lamp remains off for 1.6 seconds between the long and short flashes.




Self-Diagnostic Inspection
Code Retrieval
The single malfunction code is only available for retrieval when the cruise indicator in the instrument cluster is lit, indicating a problem with the cruise control system. Turning the ignition key OFF with the cruise indicator lit will clear the code from memory. To retrieve the code, follow the steps listed below.
1. Do not turn the ignition switch OFF.
2. Connect a jumper wire between test terminal C125/17 and GND terminal C125/12 in the data link connector.
3. Observe the cruise control indicator in the instrument cluster.




Self-diagnosis of malfunction
The cruise indicator will flash if a malfunction is present.