wiring issue
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wiring issue
Not sure if you can help or not but here goes. I parked my truck for 3 days. 2003 F150 when I started it the service engine soon light was on and no wipers, dome lights or blinkers. After some reading I seen where it was likely the GEM, so after some manoeuvring I was able to replace it with the same model #. Still the same issue, went in to see Ford and they said it would need programming, but my Data port isn't working either. So came to the conclusion it may be G203. Looked behind the right kick plate and found 2 black wires (I am assuming they are grounds) connected to a bolt on the outer fender. They appear corroded so I plan to cut and replace the ends to see if this works (after I put my old GEM back in). My question is... Is this G203 and if this doesn't work any ideas. Main goal right now is to get data port working. And it is not the fuse.
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I will check that first, thank you. I have a multi meter, which setting should I use?
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I don't know what meter you have.
Look on the dial for a range that will measure 12 volts DC or more.
Then look on the meter for the scale that represents that range.
Read the scale for the voltage.
If it's an auto ranging DVM there may not be any scale but a direct readout in voltage.
Good luck.
Look on the dial for a range that will measure 12 volts DC or more.
Then look on the meter for the scale that represents that range.
Read the scale for the voltage.
If it's an auto ranging DVM there may not be any scale but a direct readout in voltage.
Good luck.
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Ok here is what I found. There was nothing before cleaning up the G203. Now I am getting a 2 to 3 volt reading on the pin 16 and the following fuses under the dash all F2.* 1,2,3,4,13,14,15, and 0 on the following 16, 18, 20, 21, 26, 27, 28 I am also getting 0 under the hood fuse box in f1.15 but the rest are reading over 12 and my battery is also reading over 12 volts. I think it may be a main power wire but how can I trace it in all that mess. Where a lot of the 0 readings have to do with the GEM I may put my old one back in to see if it was just the main G203 ground. What do you think
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Lead Driver
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Stop.
Assuming your using the voltmeter correctly, your missing main power to many fuse positions on the interior fuse block.
A ground won't be the problem.
If no fuses were found blown, there are no shorts either.
You need to get power back to all those fuses before anything else is addressed.
It appears a Rodent has chewed the wires in half behind the fuse panel or even the main harness supply coming the through the firewall.
Look at the fuse lineup in your book and see they are in common rows.
Don't dismiss this happening in the engine bay as well.
Your lucky the truck has not gone up in flames from short circuits.
Good luck.
Assuming your using the voltmeter correctly, your missing main power to many fuse positions on the interior fuse block.
A ground won't be the problem.
If no fuses were found blown, there are no shorts either.
You need to get power back to all those fuses before anything else is addressed.
It appears a Rodent has chewed the wires in half behind the fuse panel or even the main harness supply coming the through the firewall.
Look at the fuse lineup in your book and see they are in common rows.
Don't dismiss this happening in the engine bay as well.
Your lucky the truck has not gone up in flames from short circuits.
Good luck.
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From: Abbotsford
Fuses 1,2,3,4,13,14,15 are powered directly off fuse 103 50A underhood, what voltage readings do you get on either side of that fuse with it plugged in? Could be a bad/corroded fuse or a corroded connection somewhere.
Have a look at the power distribution wiring diagram and trace it back.
Search Wiring Diagrams
Have a look at the power distribution wiring diagram and trace it back.
Search Wiring Diagrams
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Thank you I will check the relay and go back to the panel to test, Then I will start tracing. It may sound weird but when I had my remote starter put in 6 years ago I had to take it back to them twice because I lost my wipers. While I was on my head under the dash replacing the GEM I seen a slice in a green wire, wires were visible but not corroded. I don't know if the dip in voltage to the top row was before or after I put in the junk yard GEM. I wish I had of tested them before I swapped them out. Thank you for your help, I only have today then my husband is forcing me to take it to a mechanic, problem is there are not many I trust. If my data port wasn't dead I would take it to ford but they seem to rely heavily on computers so no point doing that until I get my data port working, it too is reading 2.67.
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Killerstroke, thank you thank you I checked fuse 103 and underneath was a broken wire. Going to fix that and re-install my old GEM. The replacement one I would say was bad but at least if I still have the same issues I can get a different one and having done it 3 times now (to include taking off the other 2) I hope to have no trouble.
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