• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

wiring problem, starting system

  • Thread starter Thread starter dastang2
  • Start date Start date Mar 9, 2007

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Mar 9, 2007
#1
  • Mar 9, 2007
  • #1
i put a new ignition switch but it still does it. i only get 7 volts from the rad and blue wire that connects to the starter solinoid. i have to jump the posts on the solinoid to start the car. doesn anybody have any ideas. it is an 89
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 9, 2007
#2
  • Mar 9, 2007
  • #2
Just for clarity, was the ignition switch or lock cylinder replaced?

I'd start at the ignition switch's electrical connector. See if the Crank wire has 12 volts there. If it does, head down to the clutch switch and see if 12 volts is making into AND out of the switch (if you wired one in while doing the swap).

That's where I'd start anyhow.
Good luck.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Mar 9, 2007
#3
  • Mar 9, 2007
  • #3
switch was replaced and there is no safety on it. the red wire that gets power when you turn the key to start position is getting 7 volts. it is red with a blue stripe
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 9, 2007
#4
  • Mar 9, 2007
  • #4
If you've tested the starter wire at the ignition switch electrical connector itself (it was a white/pink wire on my '88 IIRC), then to me that suggests a bad switch (new or not).
Have you confirmed that the ignition fusible links are in good shape? Just in case the issue is upstream of the ignition switch itself...........

Good luck.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Mar 16, 2007
#5
  • Mar 16, 2007
  • #5
i temporarily deleted those fusible links with wire, that is not it. ok i thought you were talking about the wire on the solinoid that pops on the front of it that gets switched power.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 16, 2007
#6
  • Mar 16, 2007
  • #6
Yeah, I had wondered if the testing of the red/blue (starting) wire was done at the ignition switch itself. This narrows things down in case you have a bad clutch switch or run of wire.

If you only have 7 volts at the starter wire (as tested at the ignition switch itself): I had pondered whether the ignition switch's power supply was corrupted (via a bad connection, fusible links, or poor conductivity inside the switch itself), wihch would cause you to only see 7 volts at the switch while cranking.

If you have 12 volts at the switch but only 7 reaching the Solenoid, the CSS or wiring as suspect.

Good luck.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
Mar 16, 2007
#7
  • Mar 16, 2007
  • #7
Some diagrams to help you....

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel pump, alternator, ignition & A/C wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Computer, actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Fuse panel layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
 

Attachments

  • fuel-alt-links-ign-ac.gif
    83.1 KB · Views: 142
  • IgnitionSwitchWiring.gif
    10.1 KB · Views: 143
You must log in or register to reply here.

Similar threads

Engine Fuel not pumping
  • Creomod
  • Apr 13, 2026
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
43
Views
695
Fox 5.0 Mustang Tech May 3, 2026
Shakerhood
S
1990 foxbody 5.0 fuel system.
  • staceyj
  • Nov 28, 2025
  • Fox 5.0 Mustang Tech
Replies
8
Views
337
Fox 5.0 Mustang Tech Nov 28, 2025
Mustang5L5
J
89 mustang alarm install to lock and unlock
  • jk66
  • Apr 9, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
4
Views
127
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Apr 10, 2026
jk66
J
A
Electrical electric mirror switch issue...
  • alchemist1
  • Apr 18, 2026
  • Fox 5.0 Mustang Tech
Replies
1
Views
91
Fox 5.0 Mustang Tech Apr 19, 2026
2000xp8
Old Ford Classic Problem
  • Potomus Pete
  • Aug 31, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
31
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Sep 8, 2024
General karthief
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?