Instrument Cluster Self-Diagnostic Mode
To enter the instrument cluster self-diagnostic mode, press and hold the instrument cluster SELECT/RESET button, turn the ignition switch to the RUN position, and then continue pressing the SELECT/RESET button (five seconds) until tESt is displayed in the odometer. The SELECT/RESET button must be released within three seconds of the odometer tESt display to begin the self-diagnostic mode. Press the SELECT/RESET button to advance through the following steps until dtc is displayed.
Depressing the SELECT/RESET button will display any stored continuous DTCs before proceeding to the next step.
| Odometer Display | Description |
| GAGE | Activates gauge sweep of all gauges, then displays present gauge values. Also carries out the checksum tests on ROM and EE. |
| All segments illuminated | Illuminates all odometer segments. |
| bulb | Illuminates all micro-controlled indicators and LEDs. Install a new indicator or LED as necessary. |
| r | Returns to normal operation of all micro-controlled indicators and LEDs and displays hexadecimal value for ROM level (used when requesting assistance from the hotline). |
| EE | Displays hexadecimal value for EE level (used when requesting assistance from the hotline). |
| dt | Displays hexadecimal coding of final manufacturing test date (used when requesting assistance from the hotline). |
| dtc | Displays continuous DTCs in hexadecimal format. Pressing the SELECT/RESET button will display any DTCs stored before proceeding to the next step. |
| enG | Displays the English speed in mph. Speedometer will indicate present speed within tolerances. Display will show 0 if input is not received, if input received is invalid for one second or more, or if speed is 0. |
| m | Displays the metric speed data (km/h). Speedometer will indicate present speed within tolerances. Display will show 0 if input is not received, if input received is invalid for one second or more, or if speed is 0. |
| tAc | Displays the tachometer data received from the PCM via the SCP network within tolerances. Tachometer will indicate present rpm. Display will show 0 if input is not received, if input received is invalid for one second or more, or if engine rpm is 0. |
| FUEL | Displays the code (0-255) for the fuel sender input to the instrument cluster. The fuel gauge will display a filtered fuel level value. This filter will keep the pointer from moving suddenly or erratically.
|
| OIL | Displays the code (0-250) for the oil pressure switch input to the instrument cluster. Oil pressure gauge will indicate present oil pressure. Normal oil pressure (greater than 6 psi) will display a value between 000 and 176. A low oil pressure or an inoperative engine oil pressure switch (less than 6 psi) will display a value greater than 176. |
| dEGC | Display of engine temperature in degrees C input from cylinder head temperature sensor.
|
| bAtt | Displays the code (0-255) for the battery voltage input to the instrument cluster. Battery voltage gauge will indicate present battery voltage.
|
| rhEo | Displays the present decimal rheostat dimming input, 0-255 (used when requesting assistance from the hotline). |
| rhi rhS rho |
Not used. |
| Cr | Displays the present RUN/START sense input. Display will show -h for high input with the ignition switch in the START position and -L for low input with the ignition switch in the RUN position. |
| PA-PE7 | Not used. |
| GAGE | Repeats test display cycle. |
To exit the instrument cluster self-diagnostic mode, turn the ignition switch to the OFF position or press and hold the SELECT/RESET button for three or more seconds and release.
Instrument Cluster Diagnostic Trouble Code (DTC) Index
| Diagnostic Tool Displayed DTC | Self-Diagnostic Mode Displayed DTC | Description | Source | Action |
| B1202 | 9202 | Fuel Sender Open Circuit | Instrument Cluster | Go To Pinpoint Test B . |
| B1204 | 9204 | Fuel Sender Short to Ground | Instrument Cluster | Go To Pinpoint Test B . |
| B1317 | 9317 | Battery Voltage High | Instrument Cluster | Section |
| B1318 | 9318 | Battery Voltage Low | Instrument Cluster | Section |
| B1342 | 9342 | ECU is Defective | Instrument Cluster | INSTALL a new instrument cluster; REFER to Instrument Cluster in this section. TEST the system for normal operation. |
| B1343 | 9343 | Heated Backlight Input Circuit Failure | Instrument Cluster | Section |
| B1356 | 9356 | Ignition Run Circuit Open | Instrument Cluster | Go To Pinpoint Test A . |
| B1364 | 9364 | Ignition Start Circuit Open | Instrument Cluster | Go To Pinpoint Test A . |
| B2143 | A143 | Odometer NVM Mmory Failure | Instrument Cluster | Go To Pinpoint Test J . |
| C1284 | 5284 | Oil Pressure Switch Failure | Instrument Cluster | Go To Pinpoint Test C . |
| P1197 | 1197 | Mileage Switch Circuit Failure | Instrument Cluster | Go To Pinpoint Test J . |
GEM Diagnostic Trouble Code (DTC) Index
| DTC | Description | Source |
| B1218 | Horn Relay Coil Circuit Short to VBatt | GEM |
| B1312 | Lamp Headlamp Input Circuit Short to Battery | GEM |
| B1317 | Battery Voltage High | GEM |
| B1318 | Battery Voltage Low | GEM |
| B1322 | Driver Door Ajar Circuit Short to Ground | GEM |
| B1330 | Passenger Door Ajar Circuit Short to Ground | GEM |
| B1334 | Decklid Ajar Rear Door Circuit Short to Ground | GEM |
| B1339 | Chime Input Request Circuit Short to Battery | GEM |
| B1340 | Chime Input Request Circuit Short to Ground | GEM |
| B1342 | ECU is Defective | GEM |
| B1353 | Ignition Key-In Circuit Open | GEM |
| B1359 | Ignition Run/Acc Circuit Failure | GEM |
| B1396 | Power Door Lock Circuit Short to Battery | GEM |
| B1397 | Power Door Unlock Circuit Short to Battery | GEM |
| B1405 | Driver Power Window Down Circuit Short to Battery | GEM |
| B1408 | Driver Power Window Up Circuit Short to Battery | GEM |
| B1426 | Lamp Safety Belt Circuit Short to Battery | GEM |
| B1428 | Lamp Safety Belt Circuit Failure | GEM |
| B1431 | Wiper Brake/Run Relay Circuit Failure | GEM |
| B1432 | Wiper Brake/Run Relay Circuit Short to Battery | GEM |
| B1434 | Wiper Hi/Low Speed Relay Coil Circuit Failure | GEM |
| B1436 | Wiper Hi/Low Speed Relay Coil Circuit Short to Battery | GEM |
| B1438 | Wiper Mode Select Switch Circuit Failure | GEM |
| B1441 | Wiper Mode Select Switch Circuit Short to Ground | GEM |
| B1446 | Wiper Park Sense Circuit Failure | GEM |
| B1448 | Wiper Park Sense Circuit Short to Battery | GEM |
| B1450 | Wiper Wash/Delay Switch Circuit Failure | GEM |
| B1453 | Wiper Wash/Delay Switch Circuit Short to Ground | GEM |
| B1458 | Wiper Washer Pump Motor Relay Circuit Failure | GEM |
| B1460 | Wiper Washer Pump Motor Relay Coil Circuit Short to Battery | GEM |
| B1462 | Safety Belt Switch Circuit Failure | GEM |
| B1466 | Wiper Hi/Low Speed Not Switching | GEM |
| B1473 | Wiper Low Speed Circuit Motor Failure | GEM |
| B1476 | Wiper High Speed Circuit Motor Failure | GEM |
| B1551 | Decklid Release Circuit Failure | GEM |
| B1553 | Decklid Release Circuit Short to Battery | GEM |
| B1555 | Ignition Run/Start Circuit Failure | GEM |
| B1687 | Lamp Dome Input Circuit Short to Battery | GEM |
| B2486 | Parklamp Output Relay Driver Circuit Failure | GEM |
| B2488 | Parklamp Output Relay Driver Short to Battery | GEM |
| C1189 | Brake Fluid Level Sensor Input Short Circuit to Ground | GEM |
| C1223 | Lamp Brake Warning Output Circuit Failure | GEM |
| C1225 | Lamp Brake Warning Output Circuit Short to Battery | GEM |
Symptom Chart
| Condition | Possible Sources | Action |
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Test yourself
A quick Ford Mustang quiz: every answer comes with an explanation and a link to the manual page.