MICU Input Test

WARNING: This page is about a different car, the 2013 Honda Fit, 2012 Honda Fit, 2011 Honda Fit, 2010 Honda Fit, and 2009 Honda Fit. However, it is still accessible from the selected car via links, so may be relevant.

Turn the ignition switch to LOCK (0).
Remove the fuse access panel (see FUSE ACCESS PANEL REMOVAL/INSTALLATION ).
Disconnect under-dash fuse/relay box connectors K, M, N and Q.
NOTE: All connector views are shown from wire side of female terminals.

Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors K, M, N & Q
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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, do these input tests at the following 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.

DTC TROUBLESHOOTING TABLE

Cavity

Wire

Test condition

Test: Desired result

Possible cause if desired result is not obtained

BLU

Under all conditions

Check for continuity between terminal Q2 and the data link connector 16P connector terminal No. 7:
There should be continuity.

An open or high resistance in the wire

LT GRN

Immobilizer-keyless control unit 7P connector disconnected

Check for continuity between terminal Q3 and the immobilizer-keyless control unit 7P connector terminal No. 4:
There should be continuity.

An open or high resistance in the wire

LT GRN

Gauge control module 32P connector disconnected

Check for continuity between terminal Q3 and the gauge control module 32P connector terminal No. 18:
There should be continuity.

An open or high resistance in the wire

Q3 ⁽¹⁾

LT GRN

HandsFreeLink control module 28P connector disconnected

Check for continuity between terminal Q3 and the HandsFreeLink control module 28P connector terminal No. 18:
There should be continuity.

An open or high resistance in the wire

⁽¹⁾	For 2012 model without navigation.

Reconnect the connectors to the under-dash fuse/relay box, turn the ignition switch to ON (II), and do these input tests at the following 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 7.

NOTE: These are power and ground tests for the multiplex integrated control unit.

DTC TROUBLESHOOTING TABLE

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
N1	PNK	Under all conditions	Measure the voltage to ground: There should be battery voltage.	Blown No. 1 (10 A) fuse in the under-dash fuse/relay box Faulty driver's under-dash fuse/ relay box An open or high resistance in the wire
Q8	LT BLU	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 22 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open or high resistance in the wire
K10	BLK	In all ignition switch positions	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G502) or an open in the ground wire 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 (G501) or an open in the ground wire 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) or an open in the ground wire 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 (G502) or an open in the ground wire An open or high resistance in the wire

If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU).
- For USA model (see USA MODELS )
- For Canada model (see CANADA MODELS )