Turn the ignition switch to LOCK (0).

RHD model: Remove the fuse lid panel , and remove the driver's dashboard lower cover.

LHD model: Remove the fuse lid panel.

Disconnect under-dash fuse/relay box connectors A, B, G, K, M, N, P, and Q.

NOTE: All connector views are shown from wire side of female terminals.

Inspect the connector and socket terminals to be sure they are all making good contact.

With the connectors still disconnected, make these input tests at the connectors.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
N2	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G501) An open in the wire
K10	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G502) An open in the wire
Q9	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G502) An open in the wire
M16	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G501) An open in the wire
Q2	BLU	Under all conditions	Check for continuity between the Q2 terminal and the data link connector (16P) connector No. 7 terminal: There should be continuity.	An open in the wire
Q2	BLU	Immobilizer-keyless control unit 7P connector disconnected	Check for continuity between the Q2 terminal and the immobilizer-keyless control unit 7P connector No. 5 terminal: There should be continuity.	An open in the wire
Q2	BLU	Audio unit connector A (24P) disconnected	Check for continuity between the Q2 terminal and audio unit connector A (24P) No. 3 terminal: There should be continuity.	An open in the wire
Q2	BLU	SRS unit connector A (39P) disconnected	Check for continuity between the Q2 terminal and SRS unit connector A (39P) No. 18 terminal: There should be continuity.	An open in the wire
Q2	BLU	ABS modulator-control unit 25P connector disconnected	Check for continuity between the Q2 terminal and the ABS modulator-control unit 25P connector No. 10 terminal: There should be continuity.	An open in the wire
Q2	BLU	VSA modulator-control unit 36P connector disconnected	Check for continuity between the Q2 terminal and the VSA modulator-control unit 36P connector No. 3 terminal: There should be continuity.	An open in the wire
Q2	BLU	EPS control unit connector C (16P) disconnected	Check for continuity between the Q2 terminal and EPS control unit connector C (16P) No. 16 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Immobilizer-keyless control unit 7P connector disconnected	Check for continuity between the Q3 terminal and the immobilizer-keyless control unit 7P connector No. 4 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Gauge control module 32P connector disconnected	Check for continuity between the Q3 terminal and the gauge control module 32P connector No. 18 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Climate control unit 36P connector disconnected	Check for continuity between the Q3 terminal and the climate control unit 36P connector No. 6 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Hands free telephone control unit 28P connector disconnected	Check for continuity between the Q3 terminal and the hands free telephone control unit 28P connector No. 18 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Headlight leveling control unit 16P connector disconnected	Check for continuity between the Q3 terminal and the headlight leveling control unit 16P connector No. 16 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Automatic lighting/rain sensor 5P connector disconnected	Check for continuity between the Q3 terminal and the automatic lighting/rain sensor 5P connector No. 5 terminal: There should be continuity.	An open in the wire
Q2	BLU	Disconnect these connectors: Immobilizer-keyless control unit 7P connector Audio unit connector A (24P) SRS unit connector A (39P) ABS modulator control unit 25P connector (Without VSA) VSA modulator control unit 36P connector (With VSA) EPS control unit connector C (16P)	Check for continuity to ground: There should be no continuity.	A short to ground in the wire
Q3	LT GRN	Disconnect these connectors: Immobilizer-keyless control unit 7P connector Gauge control module 32P connector Climate control unit 36P connector (With climate control) Hands free telephone control unit 28P connector (With hands free telephone system) Headlight leveling control unit 16P connector (With HID) Automatic lighting/rain sensor 5P connector (With automatic lighting/automatic wiper system)	Check for continuity to ground: There should be no continuity.	A short to ground in the wire

Reconnect the connectors to the under-dash fuse/relay box, and make these input tests at the connector.

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 under-dash fuse/relay box An open in the wire
M18	PUR	Ignition switch ACC (I)	Measure the voltage to ground: There should be battery voltage.	Blown No. 14 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
K8	RED	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 20 (15 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open 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 in the wire
P2	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 6 (10 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
A32	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 11 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
B11	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 11 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
Q14	BRN	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 10 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
A31	LT GRN	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 5 (10 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
G5	LT BLU	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 under-dash fuse/relay box An open in the wire

If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU). If input failures are related to a particular control unit, replace the control unit.

Turn the ignition switch to LOCK (0).

RHD model: Remove the fuse lid panel , and remove the driver's dashboard lower cover.

LHD model: Remove the fuse lid panel.

Disconnect under-dash fuse/relay box connectors A, B, G, K, M, N, P, and Q.

NOTE: All connector views are shown from wire side of female terminals.

Inspect the connector and socket terminals to be sure they are all making good contact.

With the connectors still disconnected, make these input tests at the connectors.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
N2	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G501) An open in the wire
K10	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G502) An open in the wire
Q9	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G502) An open in the wire
M16	BLK	Under all conditions	Check for continuity to ground: There should be continuity.	Poor ground (G501) An open in the wire
Q2	BLU	Under all conditions	Check for continuity between the Q2 terminal and the data link connector (16P) connector No. 7 terminal: There should be continuity.	An open in the wire
Q2	BLU	Immobilizer-keyless control unit 7P connector disconnected	Check for continuity between the Q2 terminal and the immobilizer-keyless control unit 7P connector No. 5 terminal: There should be continuity.	An open in the wire
Q2	BLU	Audio unit connector A (24P) disconnected	Check for continuity between the Q2 terminal and audio unit connector A (24P) No. 3 terminal: There should be continuity.	An open in the wire
Q2	BLU	SRS unit connector A (39P) disconnected	Check for continuity between the Q2 terminal and SRS unit connector A (39P) No. 18 terminal: There should be continuity.	An open in the wire
Q2	BLU	ABS modulator-control unit 25P connector disconnected	Check for continuity between the Q2 terminal and the ABS modulator-control unit 25P connector No. 10 terminal: There should be continuity.	An open in the wire
Q2	BLU	VSA modulator-control unit 36P connector disconnected	Check for continuity between the Q2 terminal and the VSA modulator-control unit 36P connector No. 3 terminal: There should be continuity.	An open in the wire
Q2	BLU	EPS control unit connector C (16P) disconnected	Check for continuity between the Q2 terminal and EPS control unit connector C (16P) No. 16 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Immobilizer-keyless control unit 7P connector disconnected	Check for continuity between the Q3 terminal and the immobilizer-keyless control unit 7P connector No. 4 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Gauge control module 32P connector disconnected	Check for continuity between the Q3 terminal and the gauge control module 32P connector No. 18 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Climate control unit 36P connector disconnected	Check for continuity between the Q3 terminal and the climate control unit 36P connector No. 6 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Hands free telephone control unit 28P connector disconnected	Check for continuity between the Q3 terminal and the hands free telephone control unit 28P connector No. 18 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Headlight leveling control unit 16P connector disconnected	Check for continuity between the Q3 terminal and the headlight leveling control unit 16P connector No. 16 terminal: There should be continuity.	An open in the wire
Q3	LT GRN	Automatic lighting/rain sensor 5P connector disconnected	Check for continuity between the Q3 terminal and the automatic lighting/rain sensor 5P connector No. 5 terminal: There should be continuity.	An open in the wire
Q2	BLU	Disconnect these connectors: Immobilizer-keyless control unit 7P connector Audio unit connector A (24P) SRS unit connector A (39P) ABS modulator control unit 25P connector (Without VSA) VSA modulator control unit 36P connector (With VSA) EPS control unit connector C (16P)	Check for continuity to ground: There should be no continuity.	A short to ground in the wire
Q3	LT GRN	Disconnect these connectors: Immobilizer-keyless control unit 7P connector Gauge control module 32P connector Climate control unit 36P connector (With climate control) Hands free telephone control unit 28P connector (With hands free telephone system) Headlight leveling control unit 16P connector (With HID) Automatic lighting/rain sensor 5P connector (With automatic lighting/automatic wiper system)	Check for continuity to ground: There should be no continuity.	A short to ground in the wire

Reconnect the connectors to the under-dash fuse/relay box, and make these input tests at the connector.

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 under-dash fuse/relay box An open in the wire
M18	PUR	Ignition switch ACC (I)	Measure the voltage to ground: There should be battery voltage.	Blown No. 14 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
K8	RED	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 20 (15 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open 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 in the wire
P2	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 6 (10 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
A32	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 11 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
B11	PUR	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 11 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
Q14	BRN	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 10 (7.5 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
A31	LT GRN	Ignition switch ON (II)	Measure the voltage to ground: There should be battery voltage.	Blown No. 5 (10 A) fuse in the under-dash fuse/relay box Faulty under-dash fuse/relay box An open in the wire
G5	LT BLU	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 under-dash fuse/relay box An open in the wire

If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU). If input failures are related to a particular control unit, replace the control unit.