Truck not shutting OFF after running in rain..

[Rawze]

(04-09-2022 )Possmguts Wrote:  Even with CECU all unplugged, still acts as if ignition is ON...
Really need some help with this.

If it is not the key-switch itself or its associated key-on relays(s), then What you will most likely find is that some device (gauge, controller, abs, dash radio, panel control, ... something...) that is wired to BOTH the +12 volts battery, AND the key-switch, that is back-feeding power from its battery circuit into the key-on circuit improperly.

The biggest offenders are usually something that did not come with the truck when it was purchased.. like aftermarket gauges, e-log devices, a hidden tracker from a leasing company, or anything else that someone has installed. That is why I asked if you had unplugged all your aftermarket gauges, etc. .. but it can also be an OEM device as well that is going bad.

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(last resort, when all the normal things that cab be unplugged, like the radio, abs, dash gauges, suspect relays that might have been in a stuck-on state, etc... have already been checked/isolated)...

That is when someone needs to get the wiring diagram out and start isolating key-on circuits (usually by cutting wires at key points on the system to see what direction the power is leading from, then soldering/heat-shrinking them back together) to find the source of the power that is remaining on when the keys-witch is off.