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Electrical questions 89 GT Convertible

  • Thread starter Thread starter gearhead77
  • Start date Start date Mar 18, 2019

gearhead77

Active Member
Mar 13, 2019
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38
Pittsburgh PA
Mar 18, 2019
#1
  • Mar 18, 2019
  • #1
So, I know that the door lock actuator is frozen on the passenger side and I haven't been able to get the passenger door open yet. But my question is this: The power door lock button doesn't work on either door but everything else is fine. I see from the Bishko manual that the door locks are protected by a circuit breaker on the starter relay. Car starts and runs fine. Is is possible the CB is blown but doesn't affect the starter relay? Will the button not work because the passenger door lock actuator is frozen?

The only other issues I have electrically that I can see or hear is that the door chime works, but is very ,very weak, nearly inaudible. Also, the radio display (original) is very dim, but the radio does work, doesn't matter if headlights are on or off. Are these problems related at all? From the wiring diagrams I went through briefly ( lousy work getting in the way) it doesn't seem so. Thanks.
 

Blown88GT

Founding Member
Nov 13, 1999
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Palm Beach Gardens, FL
Mar 18, 2019
#2
  • Mar 18, 2019
  • #2
If the power windows work, it's not the circuit breaker.
If the door mechanical mechanism is all gummed up, the actuator won't have enough power to override.

Weak chime & dim radio indicates maybe a bad fuselink. They can partially "blow", creating increased resistance & a voltage drop.

"Bishko manual " - never heard of it.
Use this:


View: https://drive.google.com/open?id=1on5czXKmpETzxUggWTGtoUuVkJT2UUxN
 
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gearhead77

Active Member
Mar 13, 2019
128
56
38
Pittsburgh PA
Mar 18, 2019
#3
  • Mar 18, 2019
  • #3
Here's the Bishko, it's a "reprint" (CD) of the Ford Shop manual for 89 Mustang

http://www.autobooksbishko.com/repair-manual.html

I appreciate the info for all of that, it'll be a few days to try it out. I've had one small victory so far. The fuel door, trunk release didn't work. One of the taillights was replaced at some point and they never reconnected the connector in the trunk for the releases. I now have a functioning fuel door and trunk release!
 
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jrichker

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Dublin GA
Mar 18, 2019
#4
  • Mar 18, 2019
  • #4
PM me your email address and I will send you a complete Ford Factory 89 Mustang electrical diagram set. The zip file is 2.5 MB and is too big to fit through Stangnet's email gateway.

The plug shapes on the diagrams match the plug shapes on the actual plug. The diagram is divided up by the layout of the car. The first diagram is for the very front of the car, and it works its way to the rear of the car page by page.

They are in a zip file format to reduce the size of the package. If you don't have Windows 7 or Windows 8, or later, you’ll need WinZip or other Windows archive tool to extract them from the zip file.. See www.majorgeeks.com - Download Freeware and Shareware Computer Utilities for a free download.

You will need the Adobe Acrobat viewer which is also a free download – www.adobe.com/products/acrobat/readstep2.html - Adobe Reader download - All versions



Follow this link to fix your door lock actuator problems

You will need the Adobe Acrobat viewer which is also a free download – http://get.adobe.com/reader/

http://www.stangnet.com/mustang-forums/attachments/door-lock-actuator-fix-pdf.88290/

Stuck with door lock actuators that don't work and don't want to pay the $50+ for a new one? Tried the junkyard ones and found that they last six months and freeze up?

A new actuator for less than $8. Fix one side for $20, do both sides for only $28. I don't sell parts, I don’t make any money off of the upgrade, I just tell you how to do it cheaply and easily.

By the way, I am still using the same $4 actuators I bought in 2002 and this is the second Mustang I have installed them in! Beat that with your fancy replacements!
 
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