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, AutomaticFACTORY OEM SERVICE PROCEDURE
Instrument Cluster DTCS
INSTRUMENT CLUSTER DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Description | Source | Perform Test |
|---|---|---|---|
| B1202 | Fuel Sender Open Circuit | Instrument Cluster | Go To PINPOINT TEST B: INCORRECT FUEL GAUGE INDICATION . |
| B1204 | Fuel Sender Short to Ground | Instrument Cluster | Go To PINPOINT TEST B: INCORRECT FUEL GAUGE INDICATION . |
| B1317 | Battery Voltage High | Instrument Cluster | GENERATORS & REGULATORS . |
| B1318 | Battery Voltage Low | Instrument Cluster | GENERATORS & REGULATORS . |
| B1343 | Heated Backlight Input Circuit Failure | Instrument Cluster | GLASS, FRAMES AND MECHANISMS . |
| B1356 | Ignition Run Circuit Open | Instrument Cluster | Go To PINPOINT TEST A: NO COMMUNICATION WITH THE INSTRUMENT CLUSTER . |
| B1364 | Ignition Start Circuit Open | Instrument Cluster | Go To PINPOINT TEST A: NO COMMUNICATION WITH THE INSTRUMENT CLUSTER . |
| B2143 | Odometer NVM Memory Failure | Instrument Cluster | Go To PINPOINT TEST J: THE ODOMETER IS INOPERATIVE . |
| C1284 | Oil Pressure Switch Failure | Instrument Cluster | Go To PINPOINT TEST C: INCORRECT OIL PRESSURE GAUGE INDICATION . |
| P1197 | Mileage Switch Circuit Failure | Instrument Cluster | Go To PINPOINT TEST J: THE ODOMETER IS INOPERATIVE . |
GEM DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Description | Source | Perform Test |
|---|---|---|---|
| B1426 | Lamp Safety Belt Circuit Short to Battery | GEM | Go To PINPOINT TEST K: THE SAFETY BELT INDICATOR IS INOPERATIVE (CHIME IS OPERATIVE)/DOES NOT OPERATE CORRECTLY . |
| B1428 | Lamp Safety Belt Circuit Failure | GEM | Go To PINPOINT TEST K: THE SAFETY BELT INDICATOR IS INOPERATIVE (CHIME IS OPERATIVE)/DOES NOT OPERATE CORRECTLY . |
| C1189 | Brake Fluid Level Sensor Input Short Circuit to Ground | GEM | Go To PINPOINT TEST O: THE BRAKE WARNING INDICATOR IS NEVER/ALWAYS ON . |
| C1223 | Lamp Brake Warning Output Circuit Failure | GEM | Go To PINPOINT TEST O: THE BRAKE WARNING INDICATOR IS NEVER/ALWAYS ON . |
| C1225 | Lamp Brake Warning Output Circuit Short to Battery | GEM | Go To PINPOINT TEST O: THE BRAKE WARNING INDICATOR IS NEVER/ALWAYS ON . |
Factory Service Tools
Use the Manual With the Right Hardware
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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.