Rear MICU Input Test
WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Before testing the rear MICU, troubleshoot the multiplex integrated control unit first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A
).
- Turn the ignition switch to LOCK (0).
- Remove the left rear trim (see TRIM REMOVAL/INSTALLATION - REAR SIDE AREA ).
- Disconnect rear fuse/relay box connectors B (34P) and C (42P).
- Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary and recheck the system.
- If the terminals look OK, go to step 5.
- With the connectors still disconnected, make these input tests at the connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 6.
INPUT TESTS REFERENCECavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained B2 LT GRN Under all conditions (Under-dash fuse/relay box connector G (6P) disconnected Check for continuity between the B2 terminal and the under-dash fuse/ relay box connector G (6P) No. 1 terminal:
There should be continuity.An open in the wire Check for continuity to ground:
There should be no continuity.A short to ground in the wire B14 LT GRN Under all conditions (Power seat control unit connector A (40P) disconnected) Check for continuity between the B14 terminal and the power seat control unit connector A (40P) No. 40 terminal:
There should be continuity.An open in the wire Check for continuity to ground:
There should be no continuity.A short to ground in the wire C16(1) LT GRN Under all conditions (Power tailgate control unit connector C (HP) disconnected) Check for continuity between the C16 terminal and the power tailgate control unit connector C(14P) No. 7 terminal:
There should be continuity.An open in the wire Check for continuity to ground:
There should be no continuity.A short to ground in the wire C32(2) LT GRN Under all conditions (AcuraLink control unit (XM receiver) connector B (16P) disconnected) Check for continuity between the C32 terminal and the (AcuraLink control unit (XM receiver) connector B (16P) No. 5 terminal:
There should be continuity.An open in the wire Check for continuity to ground:
There should be no continuity.A short to ground in the wire (1) With power tailgate (2) With AcuraLink - Reconnect the connectors, and make these input tests at the connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, the rear MICU must be faulty, replace the rear fuse/relay box (see REMOVAL AND INSTALLATION ).
INPUT TESTS REFERENCECavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained B18 BLK Under all conditions Measure the voltage to ground:
There should be less than 0.5 V.- Poor ground (G603, G604)
- An open in the wire
B29 B4 WHT Under all conditions Measure the voltage to ground:
There should be battery voltage.- Blown No. 4 (40 A) fuse in the main under-hood fuse box
- Blown No. 7 (10 A) fuse in the under-dash fuse/relay box
- Faulty under-dash fuse/relay box
- Faulty rear fuse/relay box
- An open in the wire
B23 YEL Ignition switch ON (ID Measure the voltage to ground:
There should be battery voltage.- Blown No. 21 (7.5 A) fuse in the under-dash fuse/relay box
- Faulty under-dash fuse/relay box
- Faulty rear fuse/relay box
- An open in the wire