Multiplex Integrated Control Unit Input Test (4D)

Multiplex Integrated Control Unit Input Test

1.	Remove the left side kick panel (LHD type) or right side kick panel (RHD type).

2.

Disconnect the under-dash fuse/relay box connectors D, E, H, I, J, K, N, P and X. UNDER-DASH FUSE/RELAY BOX CONNECTOR D (17P)UNDER-DASH FUSE/RELAY BOX CONNECTOR E (16P)UNDER-DASH FUSE/RELAY BOX CONNECTOR H (14P)UNDER-DASH FUSE/RELAY BOX CONNECTOR I (5P)UNDER-DASH FUSE/RELAY BOX CONNECTOR K (12P)UNDER-DASH FUSE/RELAY BOX CONNECTOR J (21P)UNDER-DASH FUSE/RELAY BOX CONNECTOR P (30P)UNDER-DASH FUSE/RELAY BOX CONNECTOR N (45P)UNDER-DASH FUSE/RELAY BOX CONNECTOR X (39P)BLUYELBLKBLKGRN/REDGRN/WHTORN*1BRN*1YELWHTLT BLULT BLUWHTYELNOTE: All connectors are wire side of female terminals.BRN/REDORN*2BRN*2*1: LHD type*2: RHD type

3.	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 4.

4.

With the connectors still disconnected from the under-hood fuse/relay box, make these input tests at the connector(s). If any test indicates a problem, find and correct the cause, then recheck the system. If all the input tests prove ok, go to 5. Cavity  Wire  Test condition  Test: Desired result  Possible cause if result is not obtained  H9  BLK  Under all conditions  Check for continuity to ground: There should be continuity.  Poor ground (G601) An open in the wire   P1*1 P14*2  BRN  Under all conditions  Check for continuity to ground: There should be continuity.  Poor ground (G502) An open in the wire   E9  BLK  Under all conditions  Check for continuity to ground: There should be continuity.  Poor ground (G601) An open in the wire   D6 · J9 · X34  YEL  Ignition switch ON (II)  Check for voltage to ground: There should be battery voltage.  Blown No. 21 (7.5A) fuse in the under-dash fuse/relay box An open in the wire   K4  GRN/WHT  Under all conditions  Check for voltage to ground: There should be battery voltage.  Blown No. 27 (20A) fuse in the under-dash fuse/relay box An open in the wire   X35  WHT  Under all conditions  Check for voltage to ground: There should be battery voltage.  Blown No. 7 (10A) fuse in the under-dash fuse/relay box An open in the wire   N22  LT BLU  Under all conditions  Check for continuity between terminal N22 and the climate control unit B (16P) connector terminal No. 14: There should be continuity.  An open in the wire   Climate control unit B (16P) connector disconnected  Check for continuity to ground: There should be no continuity.  Short to ground   J4  BRN/RED  Under all conditions  Check for continuity between terminal J4 and power window master switch 23P connector terminal No. 16: There should be continuity.  An open in the wire   Power window master switch 23P connector disconnected  Check for continuity to ground: There should be no continuity.  Short to ground   D11  BLU  Under all conditions  Check for continuity between terminal D11 and relay module J (10P) connector terminal No. 7: There should be continuity.  An open in the wire   Relay module J (10P) connector disconnected  Check for continuity to ground: There should be no continuity.  Short to ground   X27  LT GRN  Under all conditions  Check for continuity between terminal X27 and wiper/washer switch 8P connector terminal No. 4: There should be continuity.  An open in the wire   Wiper/washer switch 8P connector disconnected  Check for continuity to ground: There should be no continuity.  Short to ground   N28  WHT  Under all conditions  Check for continuity between terminal N28 and gauge assembly (30P) connector terminal No. 25: There should be continuity.  An open in the wire   Gauge control module B (30P) connector disconnected  Check for continuity to ground: There should be no continuity.  Short to ground   *1:  LHD type  *2:  RHD type

5.

Reconnect the connectors to the under-dash fuse/relay box, and make sure these input tests at the appropriate connectors on the under-dash fuse/relay box. If any test indicates a problem, find and correct the cause, then recheck the system. If all the input tests prove OK, the multiplex integrated contorl unit must be faulty, replace the under-dash fuse/relay box assembly. Cavity  Wire  Test condition  Test: Desired result  Possible cause if result is not obtained  P7*1 P8*2  ORN  Under all conditions  Attach to ground: The ignition key light should come on.  Blown No. 13 (20A) fuse in the under-hood fuse/relay box Blown LED An open in the wire   I4  GRN/RED  Ceiling light switch in the middle position, all doors closed  Attach to ground: The ceiling light should come on.  Blown No. 6 (7.5A) fuse in the under-dash fuse/relay box Faulty ceiling light An open in the wire   *1:  LHD type  *2:  RHD type