Flow Chart No. 4: Door Locks Operate One Way Only

Flow Chart No. 4 - Symptom - Door locks operate one way only.

Step 1
Check lock operation.
1. Actuate door lock switch to lock position.




2. Did doors lock?

Step 2




Check supply to all lock relay.
1. Remove all lock relay from relay module No. 1.
2. Check for voltage at B/W pins as shown in figure.




3. Is battery voltage present?

Step 3
Check ground to all lock relay.




1. Connect ohmmeter between B circuit of all lock relay connector and known good ground as shown in figure. Measure resistance.




2. Is resistance 5 ohms or less?

Step 4
Check lock signal to all lock relay.




1. Connect ohmmeter between Ply circuit of all lock relay connector and known good ground as shown. Actuate door lock switch to lock position.
2. Measure resistance.




3. Is resistance 5 ohms or less?

Step 5




Check relay coil ground circuit.
1. Remove door lock switch, then, using a jumper, connect P/Y circuit and B circuit of door lock switch connector.
2. Connect ohmmeter between P/Y circuit of all lock relay connector and known good ground. Measure resistance.




3. Is resistance 5 ohms or less?

Step 6




Check supply to all unlock relay.
1. Remove all unlock relay from relay module No. 1.
2. Check for voltage at B/W pins as shown in figure.




3. Is battery voltage present?

Step 7
Check ground to all unlock relay.




1. Connect ohmmeter between B circuit of all unlock relay connector and known good ground as shown in figure. Measure resistance.




2. Is resistance 5 ohms or less?

Step 8
Check unlock signal to all unlock relay.




1. Connect ohmmeter between P/LG circuit of all unlock relay connector and known good ground as shown. Actuate door lock switch to unlock position.
2. Measure resistance.




3. Is resistance 5 ohms or less?

Step 9
Check relay coil ground circuit.
1. Remove door lock switch, then, using a jumper, connect P/LG circuit and B circuit of door lock switch connector.




2. Connect ohmmeter between P/LG circuit of all unlock relay connector and known good ground. Measure resistance.




3. Is resistance 5 ohms or less?