Episode 2 mystery ignition episodes in GMC

We have 2 way radios and strobes added to our vehicles. 2003 GMC Savanna van, the guy wanted a power point added in the rear for a spotlight. I tapped off the aftermarket 2 way radio power and now if the light is plugged in, when you turn off the ignition, the van keeps running if the light is plugged into the power socket. Workaround, unplug the light when you are done with it.



Today in a new GMC pickup radio guy installed radio and strobes. When the car was moved after install the key did not turn off the car, and the engine kept running, until the engineer opened the car door.



After the installer recall I asked him about the van issue and he suggested putting in a relay.



Evidently the rechargeable spotlight or any other device in the circuit can allow enough current to flow to keep the ignition running even if you turn off the ignition with the key.



Just an interesting FYI if you need it.