Question about 1999 Ford Mustang Cobra
The power door locks on my 1999 Mustang do not work. When you try to lock you hear the sound and see a jump in the lock but no lock or unlock. The remote will not lock them either. The passenger side door will on occasion lock that door but will not unlock with the switch. I guess it is possible that both switches went out about the same time but I thought it was unusual. I called the dealership to ask about a relay and they first told me that there was one but I would have to bring it in. Of course, they want that $40 per hour to fix something that I could fix myself. After talking a few minutes they then told me that mayber there wasn't a relay and I still needed to bring it in. Tired of fooling with them!! Do you have any ideas on what it could be other than maybe both switches being bad? I do not have a fuse layout so I do not know which ones to check. I don;t think it is a fuse because I do get some noice and motion from them.
If you have a test light or voltmeter I'll try and walk you thru this.
How your system works is the switch has power to it from fuse 19 in the under dash fuse panel(15amp) on the WH/VT wire,this is the same on both switches.
when you go to the lock postion the drivers switch will get power on the VT wire and in the unlock postion it will get power on the LG wire. On the passenger switch in the lock postion it will get power on the PK/YEand in unlock on the PK/LG.
Now this will fed to the GEM module which piggy backs onto the fuse panel.Then the GEM will provide power and ground to the door lock actuators in the door.
Now if you have power leaving the switch like stated I would then remove one of the door panels to access one of the actuators. Then measure voltage and ground at the actuators while you activate the door lock switch.It should have power on one side and ground on the other in one postion then when you go to the other postion on the switch this should switch, previous wire that was hot should now be ground and previous ground should now be hot.
Make sure you test it for ground as well as power you can do this by hooking your test light to a power source instead of ground and when u get a ground of course it will light.
Now the test I just provided will eliminate the door lock switches and the door lock actuators. If you do not have the power and grounds as listed then the problem will be either wiring or GEM module.
Posted on Feb 03, 2009
Tips for a great answer:
Jan 06, 2016 | Cars & Trucks
Sep 29, 2014 | 2000 Ford Explorer
Oct 02, 2012 | 1999 Ford Expedition
Jun 25, 2012 | 1999 Dodge Stratus
Dec 22, 2009 | 2003 Kia Sorento
Oct 15, 2009 | Pontiac Bonneville Cars & Trucks
Jun 30, 2009 | 2007 Chevrolet Malibu SS Sedan New Cars
Mar 07, 2009 | 1999 BMW 323 Series
676 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: