Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2004 Ford Mustang Mach 1, StandardFACTORY OEM SERVICE PROCEDURE
Warning Devices
WARNING DEVICES (GEM) DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Description | Source | Action |
|---|---|---|---|
| B1340 | Chime Input Request Circuit Short to Ground | GEM | Go To PINPOINT TEST C: A CHIME DOES NOT OPERATE CORRECTLY-AIR BAG . |
| B1342 | ECU Is Defective | GEM | CLEAR the DTCs. TEST the system for normal operation. RETRIEVE the DTCs. If DTC B1342 is retrieved, INSTALL a new GEM. REFER to MULTIFUNCTION ELECTRONIC MODULE . |
| B1353 | Ignition Key-In Circuit Open | GEM | Go To PINPOINT TEST B: THE KEY-IN-IGNITION CHIME DOES NOT OPERATE CORRECTLY . |
| B1462 | Safety Belt Switch Circuit Failure | GEM | Go To PINPOINT TEST F: THE SAFETY BELT WARNING CHIME DOES NOT OPERATE CORRECTLY . |
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
Comes to youSame-day available12-month warranty
Get a Free QuoteNo obligation. See pricing before you book.