Noticed my instrument panel lights are out when I turned on my headlights. Got home and pulled the dimmer switch on the dash. Found that there’s no power in the harness on the back of the dimmer switch. The fuse is NOT blown. So I checked for voltage on the fuse connection - No voltage there! (And my taillights are out also because they’re on the same circuit.) So now I’m wondering what feeds power to this circuit? Is this an ICU issue? Had a problem with that a few years ago…
Any advice or suggestions for what to try next is greatly appreciated. Thanks!
Fixed! Downloaded free service manual from hondahookup dot com which included electrical diagrams. Taillights and instrument panel lights are fed through circuit #11 which gets power from the combo (headlight) switch on the steering column.
Removed the plastic trim shells from the steering column. Removed and checked the functionality of the combo switch with multimeter and saw no problems. Traced the combo harness till it disappeared behind the fuse panel. So pulled the trim off from around the fuse panel, detached the fuse panel from the body wall and disconnected all the harnesses from the fuse panel (after disconnecting the battery).
Found a loose connector on the back of the fuse panel with some black discoloration on one wire socket. That wire socket had the same wire (red/green) coming from the combo harness pin D. Elec. diagram also called out red/green wire color feeding circuit #11. Verified continuity in the harness from the combo socket to the connector at the back of the fuse panel. Checked OK.
Also checked for continuity from the pin on the back of the fuse panel to the fuse plug for circuit #11 on the front of the panel. That was ok too. I’m guessing the connector came loose and arced before completely disconnecting from the back of the fuse panel. That’s when my instrument panel lights must have gone out.
Reconnected all the harnesses and verified continuity from the combo switch harness all the way to the fuse plug for circuit #11. Checked ok. Reattached the battery, the combo switch and the dimmer switch for the gauge lights. Turned on the headlights and the instrument panel lights worked. Woo woo! Problem solved.
When reconnecting the harness on the fuse panel, I found it was a lot easier without the metal dashboard knee plate there. But taking out the knee plate required removing the trim from below the steering wheel and the trim from the lower center dash surrounding the gear shift (which required loosening the left side of the right hand lower dash trim). Also cutting some of the electrical tape bundling around the harnesses improved flexibility when reattaching the harnesses. Still not a fun job upside down on my back / shoulders with my head under the dash. But it was definitely easier. And it didn’t take as long as I thought to put all the trim back in place after.
Took the better half to get ice cream in the newly fixed car. All’s well that ends well.