Dave (Bitsyncmaster) Dome Light Timer - Interior Lights only work with key "on" ?

[jawn101]

I've had this solid state dome light module installed for years - maybe 4 or 5. Has been working fine - until, today I programmed it to “parade” mode for, well, a parade. When I got home, I was cleaning up the car and tried to put it back into standard “battery saver mode” but realized that for some reason, the dome lights were no longer flashing.

Some troubleshooting with a multimeter has turned up that now, for some reason, my dome lights only work with the key set to ‘on’ (first position)

I’m not sure what could have caused this - it was working totally fine before the parade today and nothing changed. I re-seated the delay module, verified that fuses 5 and 12 are clean and seated properly, etc.

The door lights (red/yellow) work when the doors are opened. The engine compartment light comes on. The trunk (hood) light does not. The glove box light is dim, unless the key is “on” - I’ve traced the circuit using the schematics and can’t figure out what the common thread is.

Any ideas?

[81dmc]

Did you check the diodes in the dome circuit?

[jawn101]

Are there diodes? They aren't on the schematic diagram. I vaguely remember there being some - the black plastic cylinders in the electrical compartment?

[81dmc]

Are there diodes? They aren't on the schematic diagram. I vaguely remember there being some - the black plastic cylinders in the electrical compartment?

There are three located in the drivers footwell, next to the accelerator pedal. They are secured right on the main harness.

[jawn101]

Yep, after I wrote that I remembered them. The red, blue and black ones in the footwell. I checked that they were connected, and removed each one. They are "diode-ing" in that current only flows one way through them. My multimeter reads "588" on each when I have them oriented properly. I reseated all three in the harness to make sure there were no loose connections. No change in behavior, dome lights still don't work.

[81dmc]

Yep, after I wrote that I remembered them. The red, blue and black ones in the footwell. I checked that they were connected, and removed each one. They are "diode-ing" in that current only flows one way through them. My multimeter reads "588" on each when I have them oriented properly. I reseated all three in the harness to make sure there were no loose connections. No change in behavior, dome lights still don't work.

I take it you have led dome lights? If so, try removing the bulbs. If nothing changes, I'd PM Dave about it. Could be a failure of the timer module itself.

[jawn101]

I do have LED lights. When you say remove them, do you mean put back the old incandescent bulbs as a test? I could try that. I did email Dave earlier as well, waiting to hear back.

[81dmc]

I do have LED lights. When you say remove them, do you mean put back the old incandescent bulbs as a test? I could try that. I did email Dave earlier as well, waiting to hear back.

Do that.

I have always upgraded to LED bulbs, but sometimes they fail with weird results.

[jawn101]

Just to close out on this; the module had gone bad somehow and a replacement addressed the issue.

[81dmc]

Glad to here that was taken care of. 👍