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MICU Input Test

NOTE:
  • Before testing, make sure the lighting system work properly.
  • Before testing, check the No. 1 (15 A), No. 20 (15 A), No. 22 (7.5 A), No. 27 (30 A), No. 35 (15 A), No. 36 (15 A), No. 38 (15A), No. 45 (7.5 A), No. 49 (15 A), No. 50 (15 A), and No. 60 (IGN) (50 A) fuses in the under-dash fuse/relay box.
  • There are two circuits that each has a pair of fuses (No. 35 and No. 49 fuses, No. 36 and No. 50 fuses). If one fuse is blown, make sure to check the other fuse in the same circuit. If necessary, replace the blown fuse(s).
  1. Turn the ignition switch to LOCK (0).
  2. Remove the fuse access panel (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ), and remove the driver's dashboard lower cover (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ).
  3. Disconnect under-dash fuse/relay box connectors A, B, C, E, F, K, M, N, Q, and W.
    NOTE: All connector views are shown from wire side of female terminals.
    Fig 1: Views Of Under-Dash Fuse/Relay Box Connectors Terminals
    G08094605Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. 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.
  5. With the connectors still disconnected, do the following input tests:
    • 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.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    E6 LT GRN Connect the battery positive terminal to terminal E6 (F2), and connect terminal F2 (E6) to body ground Check actuator operation: The driver's door lock actuator should unlock (or lock).
    • Faulty driver's door lock actuator
    • An open or high resistance in the wire
    F2 PNK
    K5 LT BLU Connect the battery positive terminal to terminal K5 (K6), and connect terminal K6 (K5) to body ground Check actuator operation: The front passenger's door lock actuator and right rear door lock actuator should lock (or unlock).
    • Faulty front passenger's door lock actuator
    • An open or high resistance in the wire
    • Faulty right rear door lock actuator
    K6 PNK
    C35 PNK Connect the battery positive terminal to terminal C35 (C36), and connect terminal C36 (C35) to body ground Check actuator operation: The left rear door lock actuator should lock (or unlock).
    • Faulty left rear door lock actuator
    • An open or high resistance in the wire
    C36 YEL
    K9 BLU Connect the battery positive terminal to terminal K9, and connect terminal M25 to body ground Check actuator operation: The hatch release actuator should work.
    • Faulty hatch release actuator
    • An open or high resistance in the wire
    • Faulty hatch release actuator relay
    • Poor ground(G801) or an open in the ground wire
    M25 YEL
    A13 BLU Under all conditions Connect terminal A13 and terminal B23 with a jumper wire: The horn should sound
    • Faulty horn
    • An open or high resistance in the wire
    • Faulty horn ground
  6. Reconnect the connectors to the under-dash fuse/relay box, and do the following input tests:
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the MICU must be faulty; replace the under-dash fuse/relay box:
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
K10 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G502)
  • An open or high resistance in the wire
M16 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G502)
  • An open or high resistance in the wire
N2 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G501)
  • An open or high resistance in the wire
Q9 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G501)
  • An open or high resistance in the wire
M23(4) GRN Under all conditions Measure the voltage to ground: There should be less than 0.2 V(3).
  • Poor ground(G503) or an open in the ground wire
  • Faulty audio-navigation unit(1) or audio unit(2)
  • An open or high resistance in the wire
C17 PNK Hatch outer handle switch pressed Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G801) or an open in the ground wire
  • An open or high resistance in the wire
  • Faulty hatch outer handle switch
B23 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
  • Blown No. 3 (20 A) fuse in the battery terminal fuse box
  • An open or high resistance in the wire
W1 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
  • Blown No. 1 (100 A) fuse in the battery terminal fuse box
  • Blown No. 60 (IGN) (50 A) fuse in the under-dash fuse/relay box
  • Faulty ignition switch
  • An open or high resistance in the wire
C33 GRY Driver's door open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty driver's door switch
  • Faulty driver's door switch ground
  • An open or high resistance in the wire
Driver's door closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door switch
  • A short to ground in the wire
C32 LT GRN Front passenger's door open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty front passenger's door switch
  • Faulty front passenger's door switch ground
  • An open or high resistance in the wire
Front passenger's door closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty front passenger's door switch
  • A short to ground in the wire
C26 PNK Left rear door open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty left rear door switch
  • Faulty left rear door switch ground
  • An open or high resistance in the wire
Left rear door closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty left rear door switch
  • A short to ground in the wire
C40 GRN Right rear door open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty right rear door switch
  • Faulty right rear door switch ground
  • An open or high resistance in the wire
Right rear door closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty right rear door switch
  • A short to ground in the wire
C22 ORN Hatch open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty hatch latch switch
  • Poor ground(G801)or an open in the ground wire
  • An open or high resistance in the wire
Hatch closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty hatch latch switch
  • A short to ground in the wire
A29(4) PUR Hood open Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty security hood switch
  • Poor ground(G403)or an open in the ground wire
  • An open or high resistance in the wire
Hood closed Measure the voltage to ground: There should be at least 5 V.
  • Faulty security hood switch
  • A short to ground in the wire
E9 YEL Driver's door lock knob switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G501)or an open in the ground wire
  • Faulty driver's door lock knob switch
  • An open or high resistance in the wire
Driver's door lock knob switch in UNLOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door lock knob switch
  • A short to ground in the wire
E2 LT BLU Driver's door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G501) or an open in the ground wire
  • Faulty driver's door lock knob switch
  • An open or high resistance in the wire
Driver's door lock knob switch in LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door lock knob switch
  • A short to ground in the wire
M24 PUR Front passenger's door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Faulty front passenger's door lock knob switch
  • An open or high resistance in the wire
  • Poor ground(G502) or an open in the ground wire
Front passenger's door lock knob switch in LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty front passenger's door lock knob switch
  • A short to ground in the wire
C45 WHT Left rear door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G702) or an open in the ground wire
  • Faulty left rear door lock knob switch
  • An open or high resistance in the wire
Left rear door lock knob switch in LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty left rear door lock knob switch
  • A short to ground in the wire
C46 GRN Right rear door lock knob switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G601) or an open in the ground wire
  • Faulty right rear door lock knob switch
  • An open or high resistance in the wire
Right rear door lock knob switch in LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty right rear door lock knob switch
  • A short to ground in the wire
M34 GRY Ignition key inserted into the ignition switch Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G502) or an open in the ground wire
  • Faulty ignition key switch
  • An open or high resistance in the wire
Ignition switch in LOCK (0), and the ignition key removed from the ignition switch Measure the voltage to ground: There should be at least 5 V.
  • Faulty ignition key switch
  • A short to ground in the wire
E3 PNK Driver's door key cylinder switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G501) or an open in the ground wire
  • Faulty driver's door key cylinder switch
  • An open or high resistance in the wire
Driver's door key cylinder switch in neutral or UNLOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door key cylinder switch
  • A short to ground in the wire
E4 GRY Driver's door key cylinder switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G501) or an open in the ground wire
  • Faulty driver's door key cylinder switch
  • An open or high resistance in the wire
Driver's door key cylinder switch in neutral or LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door key cylinder switch
  • A short to ground in the wire
E8 GRN Driver's door lock switch in LOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground(G501) or an open in the ground wire
  • Faulty driver's door lock switch
  • An open or high resistance in the wire
Driver's door lock switch in neutral or UNLOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door lock switch
  • A short to ground in the wire
E1 WHT Driver's door lock switch in UNLOCK Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G501) or an open in the ground wire
  • Faulty driver's door lock switch
  • An open or high resistance in the wire
Driver's door lock switch in neutral or LOCK Measure the voltage to ground: There should be at least 5 V.
  • Faulty driver's door lock switch
  • A short to ground in the wire
(1) With navigation
(2) Without navigation
(3) If the factory-installed audio unit or audio-navigation unit is removed from the vehicle, this voltage will be between 10-12V.
(4) With security
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