OK, here's what I did: I installed a 2-way Ham radio in a 2000 Silverado. I wired directly through the firewall to the battery. Since that was done, an intermittent problem has occurred: On keying the ignition, all power to the truck is killed for up to 10 minutes. The only think that works is the 2-way radio. After the ten minutes, power is restored. In looking at the vehicle's manual, there is a statement that any additional electronics installed could affect other system electronics, including starting. I don't see how this could possibly happen if the unit is installed to the battery. This happened approximately once in every 10 starts, but after I disconnected the radio, it has not occurred at all with at least 30 starts of the truck. Coincidence?
The only thing I can think of that could be a problem is the electromagnetic interference from the radio may be causing a problem with the passlock system or an onboard computer, "fooling" the vehicle into thinking someone is trying to steal it.Also make sure you have a good solid ground point.I would make sure that the radio is off before trying to start the vehicle, also this might sound silly, but make sure you are not leaving the radio on for extended periods of time therefore draining the battery.
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My mechanic told me, "I couldn't fix your brakes, so I made your horn louder"