These instructions apply to the Ford Mustang Mk5 (S197) 2005-2014.
For other models, please choose your vehicle here.
Before electrical work on a 2005–2014 Ford Mustang you disconnect the 12 V battery, negative first. The engine relearns its idle afterward. This is the US-market procedure.
- Ignition off, key out, eye protection on.
- Open the hood; the battery is in the engine compartment (group 96R).
- Remove the negative (−, black) cable first, then the positive (+, red).
- Reconnect positive first, negative last.
- Reset the clock and radio, then idle to temperature and drive about 10 miles so the idle and transmission strategies relearn.
FAQ
Which cable first?
Negative off first, negative on last.
Why does it run rough at first?
The engine relearns its idle and fuel trims after a disconnect; firm shifts are normal until the transmission relearns.
What battery does it use?
A group-96R battery (BXT-96R); the manual lists the part, not a CCA figure.
If your Mustang stores a fault code with the warning light, look it up on autodtcs.com.
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