my stang is having electrical problems...PLEASE HELP!!

[Rasikajay]

Hi everyone, my 2003 mustang GT is having electrical problems. My brake lights and signals are not working but my headlights are working. My power windows and horn are working but my power locks are not working. Also my radio has no power and my my wipers are not working. I checked all the fuses and they are working and my battery is good. I think I have a lose connection. Also the previous owner had satellite radio installed and he took it out before he sold it to me. What should I do? Please Help!!!

 

[wmburns]

Check ground G203/G204 center console

There is a ground G203/G204 is around the center console. Several pieces of equipment including the radio, CCRM, and others use this ground. Likely it is not connected or came loose.

IMO, all of your problems can be explained by a problem with this ground. The CCRM controls many devices including wipers, door locks, Radio, and others. Therefore, no ground to the CCRM will cause a multidue of problems.

Start with a visual inspection. Post the results. Otherwise, some additional tests will help confirm the problem.

Do you have a volt-ohm-meter (VOM)? Are you willing to use it?

 

[Rasikajay]

There is a ground G203/G204 is around the center console. Several pieces of equipment including the radio, CCRM, and others use this ground. Likely it is not connected or came loose.

IMO, all of your problems can be explained by a problem with this ground. The CCRM controls many devices including wipers, door locks, Radio, and others. Therefore, no ground to the CCRM will cause a multidue of problems.

Start with a visual inspection. Post the results. Otherwise, some additional tests will help confirm the problem.

Do you have a volt-ohm-meter (VOM)? Are you willing to use it?

I used my uncle's VOM to check all the fuses and they all were working. Now my battery just died.... oh yea, thanks for that diagram, i'm gonna check out and see if the grounds on the diagram and see if they have a lose connection.

 

[wmburns]

I thought about it some more. All of your problems except for the brake lights can be explained by the missing ground. The brake lights pass battery voltage directly through the various switches and such (no relays). The grounds for the brake lights are in the rear of the car.

The turn signals and wipers are user controlled using the multi-function switch. The multi-function switch tells the CCRM what to do. It is the CCRM that is the actual power relays for the wiper motors and turn signals. So the missing ground for the CCRM makes sense.

OBTW, the electronic flasher module uses ground G204 as well.

If the brake lights do not work, check fuse F2.33(15a) and F2.41(15a) in the Centeral Junction Box (CJB). Otherwise, the brake lights may be a separate problem. Are you positive that the brake lights do not work?

Are there any other mods that can explain the dead battery? Of course it could be the CCRM is responsible for the time delay features (exit lights, radio working after key off). If the CCRM is not working correctly, it is possible the dome light (or some other delay acc) is draining the battery.

 

[Rasikajay]

All my fuses are good and all my grounds are good too. Do you think my computer is fried? Should I take it to a shop?

 

[wmburns]

That depends. How did you test the ground (visual or test with VOM)?

At the risk of offending, IMO, in light of the situation as explained in the post (car in basically good repair, problems began after removal of Sat radio, Various electrical devices that share the same ground quit working at the same time), it is highly unlikely that a GEM and CCRM failed at the same time.

Electrical trouble shooting is something I am fairly good at. With a complete set of electrial diagrams and a good understanding of electrical trouble shooting, I can help. But, this will require some detailed testing to narrow it down. The test results will have to be posted in detail.

In closing, before taking it to the shop, follow the ground wires back from the ground connection at the center console. Look for the possibility the prior owner cut the wires as part of the radio removal.

Also, double check the fuses. There are numerious electrical posts where a fuse appeared good but in fact was blown.

Good luck.

 

[Rasikajay]

Hey man,
Its turns out there was a lose connection by the left front tire. It cost me $250 becuase it took them 4 hours to find the problem.