Anyone have experience with electrical systems? My car sits for 4 or 5 days and my battery goes completely dead. Other than checking the battery and alternator anyone have an idea what it might be. Tom
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Please help with problem
- Thread starter 1TuffCobra
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Could be any kind of drain-- not sure if Roush car might have some "courtesy" lights not on regular Mustangs. Or alarm system (do you have an aftermarket system?). You can check for a draw when everythings off by hooking up an ammeter between one battery terminal and its cable. To avoid resetting your computer, you can hook it in before you remove the cable. If there's a draw you can remove fuses, using a wiring guide, to see what circuit is shorted.
Internal shorts in the battery are really common, though.
Internal shorts in the battery are really common, though.
My computer was reflashed by PHP. Are you telling me that if I disconnect my battery it will reset my computer? I guess my best bet is to take it to Ford and have them check everything out. Tom
Have your Ford dealer do a load test on your battery. mine had a dead cell from the factory. It took longer than 4 days to die but it was still bad. Luckily this was the only thing that has been wrong with my car so far.
Thanks, and I hope that mine is simple is that also. Tom
1Tuff,
Don't mean disconnecting the battery will reprogram or erase your computer. What will happen is that settings (A/F, timing, etc.) will revert to starting point of your PHP tune. ECU's do "adaptive" learning through time and optimize the settings. When you disconnect, the ECU has to relearn the optimum settings, so you'll lose a little performance or efficiency for awhile. No big deal.
Don't mean disconnecting the battery will reprogram or erase your computer. What will happen is that settings (A/F, timing, etc.) will revert to starting point of your PHP tune. ECU's do "adaptive" learning through time and optimize the settings. When you disconnect, the ECU has to relearn the optimum settings, so you'll lose a little performance or efficiency for awhile. No big deal.
1Tuff,
Don't mean disconnecting the battery will reprogram or erase your computer. What will happen is that settings (A/F, timing, etc.) will revert to starting point of your PHP tune. ECU's do "adaptive" learning through time and optimize the settings. When you disconnect, the ECU has to relearn the optimum settings, so you'll lose a little performance or efficiency for awhile. No big deal.
Would think twice (or maybe more) about taking your car back to Ford if you've had your computer reprogrammed, or other mods that might cause warantee problems. Might consider reverting your computer back to stock before taking it in, or having someone else check out your problem so as not to risk your warantee.
Don't mean disconnecting the battery will reprogram or erase your computer. What will happen is that settings (A/F, timing, etc.) will revert to starting point of your PHP tune. ECU's do "adaptive" learning through time and optimize the settings. When you disconnect, the ECU has to relearn the optimum settings, so you'll lose a little performance or efficiency for awhile. No big deal.
Would think twice (or maybe more) about taking your car back to Ford if you've had your computer reprogrammed, or other mods that might cause warantee problems. Might consider reverting your computer back to stock before taking it in, or having someone else check out your problem so as not to risk your warantee.
Tom, id hesitate to bring it straight back to Ford. I would call Roush first, before jumping the gun. Maybe even contact PHP. They may can give you some ideas. Not sure how that would go over. I know the Roush has warrantee, but Ford may not like the fact that PHP did a retune.
You guys should see that car. Its badass. Black cobra roush stg 3. Awsome ride.
You guys should see that car. Its badass. Black cobra roush stg 3. Awsome ride.
Thanks Benaa, I thought I would take the battery out and take it somewhere to have a load test done on it. PHP suggest that I do this. I am hoping that it is just the battery. If it is the battery than Ford where just give me a new one. Tom
before doing a load test, check to see if you have a drain on the battery. do this with a test light
Mine does the same thing if it sits for a few days. Found out that it was my radar detector and my cell phone charger. Even after unplugging the radar detector, the same thing would happen just not as quickly. For whatever reason, the charger would still maintain a load even though the phone was not plugged in. Just suggesting simple things to check.
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