'03 Current Surges when heater grid cycles

[tbush]

I've been experiencing a phenomenon in my 2003 HO truck for the last 2 winters that the dealer hasn't been able to explain. When I start driving to work in the mornings the radio will suddenly change radio stations, sometimes the volume of the radio changes... usually louder... . and this morning I also noticed a flicker of the lights on the dash along with the change in radio stations.



The symptoms coincide with the heater grid cycling so I'm guessing that this is causing either a current surge or a voltage spike in the dash harnessing. The dealer says that I may need to get the ECM reprogrammed. I haven't opted to go this route just yet.



Was wondering if anyone else out there is experiencing this sort of problem and if so how it was resolved.



Thanks,

TJ

 

[jkern]

put a volt meter on it

and check the battery voltage when this is occuring... my guess is that you actually have a low voltage condition that is causing the reset and changes in the radio. you didn't specify if the dash lights were getting dimmer or brighter, but that would let you know which way the voltage is going. one other but really rare possibilty is a non or very slow to function voltage regulator... these are built into the alternator, so it may need re-built or a new one.