Without Scan Tool
When trying to verify a speed control system electronic malfunction, one of two methods may be used and are described as follows:If a DRB II Diagnostic tool is not available, check for fault (trouble) codes as follows:
1. Cycle ignition switch to On position three times. On third cycle, leave switch in On position.
2. Observe Check Engine indicator on instrument cluster. If a fault (trouble) code is present, indicator lamp will flash (blink) in a series which will show which fault (trouble) code is the problem.
3. If fault (trouble) code 34 is observed, determine source of problem by performing tests, refer to SPEED CONTROL SYSTEM TESTS. Refer to SCHEMATIC DIAGRAMS/ELECTRICAL AND ELECTRONIC DIAGRAMS for speed control system wiring diagrams.
4. If fault (trouble) code 15 is present, testing of the distance sensor is required. Testing of the distance sensor requires the use of the DRB II diagnostic tool.
5. On 1991 Dodge Monaco & Eagle Premier, if fault (trouble) code 77 is present, refer to Cruise Control/Cruise Control Relay/Testing and Inspection/Procedures.
6. On all models, if no problems were found, replace engine controller.