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P16DD




DTC Troubleshooting: P16DD

DTC P16DD: Electric Vacuum Pump Relay 1 Stuck ON

1. Turn the ignition switch to LOCK (0).

2. Remove electric vacuum pump relay 1, and check it. Testing and Inspection

Is the relay OK?
YES - Go to step 3.

NO - Replace electric vacuum pump relay 1.


3. Remove the No. 17 (15 A) fuse from the under-hood fuse/relay box and the No. 31 (7.5 A) fuse from the auxiliary under-hood fuse/relay box.

4. Check for continuity between electric vacuum pump relay 1 terminals No. 1 and No. 2.

Is there continuity?
YES - Repair short in the wires between electric vacuum pump relay 1 terminals No. 1 and No. 2.

NO - Go to step 5.






5. Jump the SCS line with the HDS.

6. Disconnect PCM connector A (44P).

7. Turn the ignition switch to ON (II).

8. Measure the voltage between body ground and PCM connector A (44P) terminal No. 13.

Is there 3.0 V or more?
YES - Repair short to power in the wire between the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box and the PCM.

NO - Go to step 9.






9. Measure the voltage between body ground and PCM connector A (44P) terminal No. 12.

Is there any voltage?
YES - Repair short to power in the wire between electric vacuum pump relays 1 and 2 and the PCM.

NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM. Service and Repair