DTC B1080: Ignition Key Switch Circuit Malfunction

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: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0), and then back ON (II).
Wait for 6 seconds or more.
Check for DTCs with the HDS.
Is DTC B1080 indicated?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
Turn the ignition switch to LOCK (0).
Disconnect under-hood fuse/relay box connector D (10P).
Turn the ignition switch ON (II).
Measure the voltage between the under-hood fuse/ relay box connector D (10P) No. 7 terminal and body ground.

Fig 1: Measuring Voltage Between Under-Hood Fuse/ Relay Box Connector D (10P) No. 7 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Substitute a known-good under-hood fuse/ relay box and recheck.

NO - Go to step 9.
Turn the ignition switch to LOCK (0).
Check for continuity between the under-hood fuse/ relay box connector D (10P) No. 7 terminal and body ground.

Fig 2: Identifying Continuity Between Under-Hood Fuse/ Relay Box Connector D (10P) No. 7 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair a short to ground in the wire. After repairing, replace the No. 21 (7.5 A) fuse in the under-dash fuse/relay box.

NO - Go to step 11.
Disconnect under-dash fuse/relay box connector D (17P).
Connect the under-dash fuse/relay box connector D (17P) No. 6 terminal and body ground with a jumper wire.

Fig 3: Identifying Under-Dash Fuse/Relay Box Connector D (17P) No. 6 Terminal And Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between the under-hood fuse/ relay box connector D (10P) No. 7 terminal and body ground.

Fig 4: Identifying Continuity Between Under-Hood Fuse/ Relay Box Connector D (10P) No. 7 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Substitute a known-good under-dash fuse/ relay box and recheck.

NO - Repair open in the wire.