in2pro

No other accessories plugged in like a radar detector?
it sounds like you are getting some serious EMI from something... most likely the alternator would be my guess....
Its a long shot but you could try removing the serpentine belt and start the vehicle and see if the interference is still there...

SabrToothSqrl

this is almsot funny... sorry... like a mystery!

what about other peoples cars, does it work in them?

my guess is alternator too

don't run your car long w/out the belt, as your coolant pump will not be pumping... i'd let the engine cool down, then run it max 1 min... or less if you can.

Curly60

jeff... nope, nothing else. the gps is it. and I must say, if you need one. Magellan is the best, hands down!! this i have learned because of this, after returning several garmins and tom-toms.

tried the serpentine belt thing, no luck.

sabertooth...the gps works everywhere else, my 99 tahoe and my wifes 06 malibu. it just wont work within a 50 foot radius of my truck while in aux. or running.

nothing to do with my alternator, as i have said, my electrical system is performing perfectly fine.

the satellite reception is lost immediately after turning the ignition key to auxiliary or turning the truck engine on. instantly cuts it out. my next guess is to contact a nasa electrical engineer.....

thank you all again for taking time to help me... somebody out here has to have the answer...

curly

73shark

If it cuts out as soon as he turns the key to run w/o starting, then doesn't that rule out the alternator?

The comment re: EMI made think about what transmits in the truck and the only thing I could think of is OnStar. Try pulling the OnStar fuse.

SabrToothSqrl

try selling the truck.... (just putting it out there)...

dh1

I would pull all the non essential fuses and put them back one at a time until you identify the circuit that is emitting the EMI. There is a chance that there would be a fault in the on board circuitry, but you would expect to get some sort of fault from that.

Curly60

Shark... truck does not have OnStar.

sabrtooth... be serious, why get rid of a truck that runs and looks new with over 111,000 miles. I have taken miticulous care of this vehicle. i just replaced the brakes for the first time at 110,000 miles and didnt even need rotors.

once more, it's NOT the electrical. its NOT any PCB's. Chevrolet swapped out everything to troubleshoot. The dealer now wants to "hardwire" my magellan to see if this works.


shark... as a moderator here, I assume you know your way around chevy.
could my truck have OnStar, but without the contol or activation buttons? or knowledge to me or the dealer, and could it be transmitting analog transmistions due to no buttons? I have learned that OnStar did not go digital until 05 or 06. My owners manual mentions nothing about it. the electrical schematic does not either. my cell phone has no problem with navigation in the truck. but does not have the awesome features as magellan.

SabrToothSqrl

I got rid of mine when the A/C went at 285,000 miles...

it would 'solve' the problem...

Maybe someone put on of these on the car:

http://hem.passagen.se/communication/gps.html

If you want to get technical; here is some reading on GPS interference:

http://www.navsys.com/papers/0006002.pdf

I don't know any other way to help than, like was said, pull some fuses 1 by 1 until it works...

You have stated that when it's off, the GPS works, so have you tested the electrical components one by one? if not... get started if you really want to solve this...

in2pro

Might try using an EM field detector....
http://www.amazon.com/ElectroSensor-.../dp/B000G82KLI


Going to have to add this to my list of cool tools....

SabrToothSqrl

i want that and a laser thermometer!

if you get one let us know how it works... it looks neat!