The diagnostic code 336-02 is generated when the Electronic Control Module (ECM) detects a difference in potential between the start/run/stop inputs to the ECM. The two inputs are in an open state until the "CR" relay is energized. When the "CR" relay is energized, the start/run/stop inputs to the ECM are connected to the digital return. A broken wire or an improper connection at one of the connectors will cause the ECM to generate this code.
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| Illustration 1 | g01023335 |
Typical circuit with EMS II | |
Test Step 1. Check for an Open in the Circuit.
- Turn the ECS to the OFF position.
- Turn the battery disconnect switch to the OFF position.
- Disconnect ECM connector J1/P1.
- Measure the resistance at the ECM connector P1 between wire F717-YL in pin P-14 and wire F716-WH in pin P-08.
Expected Result:
The resistance measures less than 5 Ohms.
Results:
- OK - The resistance measures less than 5 Ohms. Proceed to Test Step 2.
- Not OK - The resistance measures more than 5 Ohms.
Repair: Check each individual wire for damage. Check the connections between the engine connector and the number two contacts of the "CR" relay. Repair the wires and/or connectors.
Stop.
Test Step 2. Check for a Short in the Circuit.
- Disconnect the "D.C. Connector No. 1 (BK)" in the panel for the EMS II.
- Measure the resistance at the ECM connector P1 between wire F717-YL in pin P-14 and engine ground.
- Measure the resistance at the ECM connector P1 between wire F716-WH in pin P-08 and engine ground.
Expected Result:
The resistance measures more than 20000 Ohms.
Results:
- OK - The resistance measures more than 20000 Ohms.
Repair: Check the wires from the "D.C. Connector No. 1 (BK)" to the number two contacts of the "CR" relay. Repair the wires.
Stop.
- Not OK - The resistance measures less than 20000 Ohms.
Repair: There is a short in one of the wires. Repair the wire.
Stop.