With Scan Tool

Refer to SCHEMATIC DIAGRAMS/ELECTRICAL AND ELECTRONIC DIAGRAMS for engine controller terminal identification and for wiring diagrams.
If a DRB II Diagnostic Tool is available, plug tool into diagnostic connector and verify that either a fault (trouble) codes 15 or 34, then refer to the appropriate set of diagnostic procedure.

The engine controller monitors critical input and output circuits within the speed control system, making sure they are operating correctly. If a problem is sensed by the controller often enough to be considered a malfunction, it is stored in the controller memory in the form of a fault (trouble) message. Fault messages are short descriptions of a defective condition that exists or of a certain circuit experiencing a malfunction. If the problem is repaired, or ceases to occur, the controller will cancel the message after 50 engine cycles.
Before starting test procedures, visually inspect speed control system for disconnected vacuum hoses, corrosion on electrical connectors, or proper cable operation. After visual inspection, perform the test procedures using the following guidelines:
1. Always start at Test 1. Starting at any other test may give incorrect results.
2. At the end of each test, reconnect all wires and hoses.
3. Ensure vehicle being tested has a fully charged battery.
4. When checking voltage or continuity at the engine controller 60-way connector, use the terminal side (not wire side) of the connector. Use care when making electrical tests to prevent accidental shorting of terminals, such mistakes can damage fuses or engine controller.
5. Perform the indicated verification test after vehicle repairs have been made.

BLANK MESSAGE SCREEN

1. Connect the DRB II to a different vehicle.
2. If message screen is still blank, the DRB II or its cable adapter are at fault. Replace as necessary.
3. If message screen is no longer blank, the DRB II and its adapter are operating satisfactory. Proceed to step 4
4. Inspect the diagnostic connector for proper wire placement, flared terminals or push outs.
5. Test BK/WT ground wire in the diagnostic connector for continuity to ground.
6. If continuity does not exist, repair open in BK/WT wire.

CARTRIDGE ERROR MESSAGE

Replace the DRB II cartridge.

KEY PAD TEST FAILURE MESSAGE

Power the DRB II up again keeping fingers off the keypad. If error message persists, replace the DRB II.

LOW OR HIGH BATTERY MESSAGE

Correct battery condition and reconnect the DRB II.

NO RESPONSE MESSAGE

1. Ensure ignition switch is in the On position.
2. Test pink and light green wires for continuity between diagnostic connector and cavities 25 and 45 on the engine controller connector.
3. Install a different DRB II with a different set of cables and check for a No Response message.
4. If steps 1 through 3 do not correct a No Response message, replace engine controller. On Mini Van models include the EMR mileage transfer. On models with theft alarm, include 20 engine starts.

RAM TEST FAILURE MESSAGE

Replace the DRB II.