1998 Z28, power draw problem.

[The_Bishop]

I'm in the process of tracking down an odd power draw problem.

When the car's shut down, key out and lights off, I'm still drawing about a tenth of an amp.

Here's where it gets odd.

If I break the battery connection, I can hear a relay click (off, I assume) and when I reconnect power, the draw is a much more reasonable .035-.036.

That relay seems to be in the passenger side of the dash, to the right of the glovebox. WTH is over there? Trying to track this one down and fix it.

Car has an aftermarket radio, installed with a crutchfield harness. Also has one of those SLP fan override switches and a front line lock. Neither the line lock or the fan switch seems to be the culprit. Edit: Car also has a racetronix hotwire kit for the fuel pump.

What relays are located in the passenger side of the dash, to the right of the glove box?

[LTb1ow]

Most of the theft deterrent stuff, ignition relay etc

[The_Bishop]

So, in further addition to the oddity... Not related to the radio, I disconnected it. Seems to be directly connected to the door lighting circuit, as the problem doesn't show until one of the doors is opened then closed. For example: Battery disconnected, doors closed, reconnect: .035-.037 amp draw. Open and close the doors, 2.4ish amps until the interior lights dim out, then a steady .97-.99 amp draw. If I break the battery connection, can hear a relay (Maybe inside BCM?) click off, reconnect battery and we're back to a .035-.037 amp draw.

I need to re-position the car so I can get the driver door opened enough to tinker with the fuses. Already did the fuse dance with the ones under the hood to no avail.

[sweetbmxrider]

Is it the accessory delay? You know, locks, windows, and radio circuits remain energized for a specific time. Usually you wait an extended period of time before checking your draw so modules etc go to sleep

[V]

Visor lights? Long shot, but I know it is a common issue with the GTOs.

[The_Bishop]

I'll see about checking those things today. I left the setup alone for a pretty long time to see if it was something like that, though. How long could the accessory delay last?

I'll check those, V. But not sure as to why they wouldn't show after a battery disconnect/reconnect... unless that's tied to the delay?

[sweetbmxrider]

I’d see how long it takes the draw to disappear, if ever. Couple hours would be plenty in my eyes. Pull main fuses, one at a time, wait 10 seconds to see if draw disappears, and once it’s found, isolate components on that circuit until the bad component is found.

[The_Bishop]

Just a followup, figured this one out. It was tune related!

I had the option turned on to run the fans for two minutes after key-off if the coolant was above 185. Now I know why the factory kept this option disabled, as it would keep the BCM powered up even after the fans shut down. Hell the BCM would stay powered up even if it didn't command the fans to run after key-off. Set it back to the factory temp setting of 255 (disabled) and all problems fixed.