Electrical Calling all wiring guys - absolute head scratcher

manicmechanic007

Active Member
Sep 26, 2017
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So now what? Pull the dash out and replace the harness. Put a factory processor back where it goes? Cluster fuchs are just that. I know because I have a 69 G code that has had extensive modification. Thank god there is only 17 wires in my main loom. You can probably still get a new harness. Otherwise marry your DVOM. Buy new old stock wire from the USA to repair your harness. Put the processor wherever you please. A lead lined box maybe
 
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rock4451

Active Member
Nov 30, 2004
12
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New Baden, IL
Pretty sure .04v between SIG RTN and batt neg terminal proves I have a short somewhere. I need to locate the short or faulty sensor.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
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That's likely phantom Voltage due to the type of multimeter being used. If you had voltage, it would be 12V, not 0.4v

 
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manicmechanic007

Active Member
Sep 26, 2017
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Splay the harness out. On a bench. You did not want to hear that. I have seen bad splices, battery acid damage, shorts melts induced voltage and the like. A good visual inspection is where you start. Pay particular attention to the processor connector for pushed out pins. You definitely have a short. Remove column pull dash (instrument panel) replace or repair harness 40 hours to start. I can have the dash out a Mustang in about 2 hours with taking smoke breaks. The harness on the other hand is arrrggghh real bad for about two days. I have never replaced one except for under warranty. A new harness front or rear is about 1800
 

rock4451

Active Member
Nov 30, 2004
12
1
29
New Baden, IL
I am going to have the MAF tested as the MAF sig and MAF RTN wires were giving me 0.11v at idle. After that I’ll take a deeper look.