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Ignition switch keeps blowing in the on positione

  • Thread starter Thread starter RJ'SDAD
  • Start date Start date Nov 10, 2019
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RJ'SDAD

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Nov 10, 2019
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Hutto, Texas
Nov 10, 2019
#1
  • Nov 10, 2019
  • #1
Hello and thank you for allowing me to be a part of this group. I have a 1989 Mustang GT which the ignition Fusible link keeps blowing when I try to turn the ignition switch to the on position. I have replaced the ignition switch harness that is connected to the steering column. I have replaced the solenoid. The car had an aftermarket alarm which all of that has been removed. I tried to jump the yellow ignition wire to the solenoid which produced the same short. The light, horn, power locks all work ,but once I place the key in the on position it blows the house fuse. I went ahead and replaced the 4 Fusible links with the correct buss fuse. .y neighbor and I are wondering what should be out next step? Thanks in advance.
 
R

RJ'SDAD

Member
Nov 10, 2019
7
3
13
Hutto, Texas
Nov 10, 2019
#2
  • Nov 10, 2019
  • #2
RJ'SDAD said:
Hello and thank you for allowing me to be a part of this group. I have a 1989 Mustang GT which the ignition Fusible link keeps blowing when I try to turn the ignition switch to the on position. I have replaced the ignition switch harness that is connected to the steering column. I have replaced the solenoid. The car had an aftermarket alarm which all of that has been removed. I tried to jump the yellow ignition wire to the solenoid which produced the same short. The light, horn, power locks all work ,but once I place the key in the on position it blows the house fuse. I went ahead and replaced the 4 Fusible links with the correct buss fuse. .y neighbor and I are wondering what should be out next step? Thanks in advance.
Click to expand...
My apologies for the poor grammar and misspellings.
 

jrichker

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#3
  • Nov 10, 2019
  • #3
Something on the switched side of the ignition has shorted battery power directly to ground. The typical troubleshooting is to disconnect all the electrical loads and add them back one load at a time until it starts blowing fuses or fuse links.



Starter solenoid wiring for 86-91 Mustang



The following are diagrams courtesy of Tmoss & Stang&2birds

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators


Ignition switch wiring
 
R

RJ'SDAD

Member
Nov 10, 2019
7
3
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Hutto, Texas
May 13, 2020
#4
  • May 13, 2020
  • #4
jrichker said:
Something on the switched side of the ignition has shorted battery power directly to ground. The typical troubleshooting is to disconnect all the electrical loads and add them back one load at a time until it starts blowing fuses or fuse links.



Starter solenoid wiring for 86-91 Mustang



The following are diagrams courtesy of Tmoss & Stang&2birds

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators


Ignition switch wiring
Click to expand...
Thanks for the diagram.
The issue was the A/C blower motor. Not sure what would cause it but running on high setting would blow the fuse. I think it might have been the build up of dust and debris. I changed it out and now the motor can run on high without any problems. This was figured out just a month ago.
 
Reactions: General karthief, 90sickfox and Olivethefet

Cheapskate207

The left one hangs a little lower
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Thanks for reporting back!
 
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