Help diagnosing beep coming from dash (1 Viewer)

[labcab]

I need some help diagnosing an intermittent issue with my ‘98 LC where I’m getting a beep from the dash.



It occurs every few weeks, starts about 10 minutes into my morning commute, continues when I turn the car off for a few hours, and is off by the time I go to lunch. I don’t get a CEL or any DTC codes.

I haven’t been able to find anything in the shop manuals identifying what the beep points to or much help searching this site or elsewhere. My latest hypothesis is that it might be due to moisture intrusion down the pillar to the panel in the footwell, but it isn’t happening directly after rain. So I figured I’d ask here before pulling the trim.

Has anyone experienced this or know where I should look in the shop manual for beeps/alarms?

 

[excessive]

id put money that it has something to do with that aftermarket head unit

 

[donco]

My 2000 LC developed a random high pitch screech while driving. I took it to the dealer and they said there was a service bulleting for it. This was back in 2004. Their solution was to snip a redundant feedback wire in the alarm system. They said they had performed a few of them at the time and there were no adverse effects with regards to the alarm going off normally when locked.

 

[labcab]

id put money that it has something to do with that aftermarket head unit

That was my first thought too and yanked the fuse to it, but the beep persisted. I put this one in a few years back, but it’s had an aftermarket head unit in it since I got it in 2003.