HDS Does Not Communicate With The MCM

Engine

IMA System Symptom Troubleshooting - HDS does not communicate with the MCM

HDS does not communicate with the MCM

NOTE: Make sure the HDS and its DLC cable are working properly.

1. PGM-FI system communication check:

PGM-FI system communication check
-1. Turn the ignition switch to LOCK (0).

-2. Connect the HDS to the DLC.

-3. Turn the ignition switch to ON (II), and read the HDS.
NOTE: If the HDS does not identify the PGM-FI system, the HDS indicates this message:

HDS has been unable to confirm connection to the vehicle.

Does the HDS identify the vehicle?
-YES- Go to step 2.
-NO- Do the DLC circuit troubleshooting for the PGM-FI system Testing and Inspection.

2. MCM power circuit check:

MCM power circuit check
-1. Turn the ignition switch to LOCK (0).

-2. Check the following fuse.





Is the fuse OK?
-YES- Go to step 3.
-NO-
* Replace the No. A13 (7.5 A) fuse in the under-hood fuse/relay box.
* Repair a short in the +B_IMA1 wire between the No. A13 (7.5 A) fuse in the under-hood fuse/relay box and the MCM (A16) and the IMA battery.

3. MCM relay 1 operation check:

MCM relay 1 operation check
-1. Remove the IPU cover.

-2. Turn the battery module switch ON.

-3. Turn the ignition switch to ON (II), and listen for a clicking sound from MCM relay 1 (A).





Is there a clicking sound?
-YES- Go to step 4.
-NO- There is a problem with MCM relay 1 or the MCM relay 1 control circuit. Go to step 10.

4. MCM relay 1 check:

MCM relay 1 check
-1. Remove MCM relay 1 (A).





-2. Test MCM relay 1 Testing and Inspection.

Is the relay OK?
-YES- Go to step 5.
-NO- Replace MCM relay 1.

5. Open wire check (+B_IMA1 line):

Open wire check (+B_IMA1 line)
-1. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The +B_IMA wire is OK. Go to step 6.
-NO- Repair an open in the wire between the No. A13 (7.5 A) fuse and MCM relay 1.

6. Determine possible failure area (IGA line or PG line, others):

Determine possible failure area (IGA line or PG line, others):
-1. Reinstall MCM relay 1.

-2. Turn the ignition switch to ON (II).

-3. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The +B_IMA wire is OK. Go to step 7.
-NO- There is a problem in the IGA line or PG line. Go to step 9.

7. Open wire check (F_CAN-H, CANH lines):

Open wire check (F_CAN-H, CANH lines)
-1. Turn the ignition switch to LOCK (0).

-2. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The F_CAN-H, CANH wires are OK. Go to step 8.
-NO- Repair an open in the F_CAN-H, CANH wire between the DLC and the MCM (A17).

8. Open wire check (F_CAN-L, CANL lines):

Open wire check (F_CAN-L, CANL lines)
-1. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The F_CAN-L, CANL wires are OK. Replace the MCM Motor Control Module (MCM) Removal And Installation.
-NO- Repair an open in the F_CAN-L, CANL wire between the DLC and the MCM (A1).

9. Open wire check (IGA line):

Open wire check (IGA line)
-1. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The IGA wire is OK. Repair an open in the PG wire between the MCM (A32) and body ground (G5).
-NO- Repair an open in the IGA wire between the MCM relay 1 and the MCM (A16).

10. MCM relay 1 check:

MCM relay 1 check
-1. Remove MCM relay 1 (A).





-2. Test MCM relay 1 Testing and Inspection.

Is the relay OK?
-YES- Go to step 11.
-NO- Replace MCM relay 1.

11. Open wire check (+B_IMA1 line):

Open wire check (+B_IMA1 line)
-1. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The +B_IMA wire is OK. Go to step 12.
-NO- Repair an open in the wire between the No. A13 (7.5 A) fuse and MCM relay 1.

12. Open wire check (IGHLD line):

Open wire check (IGHLD line):
-1. Reinstall MCM relay 1.

-2. Turn the ignition switch to ON (II).

-3. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- Repair an open in the IGHLD wire between MCM relay 1 and the MCM (A12).
-NO- The IGHLD wire is OK. Go to step 13.

13. Open wire check (PG line):

Open wire check (PG line)
-1. Turn the ignition switch to LOCK (0).

-2. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The PG wire is OK. Go to step 14.
-NO- Repair an open in the PG wire between the MCM (A32) and the body ground (G5).

14. Open wire check (IG1 line):

Open wire check (IG1 line)
-1. Turn the ignition switch to ON (II).

-2. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The IG1 wire is OK. Go to step 15.
-NO- Repair an open in the IG1 wire between the No. B5 (7.5 A) fuse in the under-dash fuse/relay box and the MCM (A29).

15. Open wire check (VBU line):

Open wire check (VBU line)
-1. Turn the ignition switch to LOCK (0).

-2. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The VBU wire is OK. Replace the MCM Motor Control Module (MCM) Removal And Installation.
-NO- Repair an open in the VBU wire between the No. A29 (10 A) fuse in the under-hood fuse/relay box and the MCM (A14).