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