bgstew6

Here ya go gents...for all that was wondering what it is and how to do it...

Instrument Cluster Dealer Test Mode
To enter the Instrument Cluster Dealer Test Mode, depress and hold the instrument cluster SELECT/RESET button and then turn the ignition switch to the RUN position. 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 displaying tESt to begin the dealer test mode. Depress the SELECT/RESET button to advance through the following steps until dtc is displayed. Depressing the SELECT/RESET button will display any continuous DTCs stored 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 lamps and LEDs (low oil pressure/high coolant temperature, low fuel, service engine soon, brake, low range). Install a new bulb or LED as necessary.
r Returns to normal operation of all micro-controlled lamps 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. Pressing the SELECT/RESET button will display any DTCs stored before proceeding to the next step.

enG Displays the 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 speed data (mph) received from the PCM via the SCP network. Displays the metric speed in kph. 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. Tachometer 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 engine rpm is 0.

FUEL Displays the actual A/D fuel level. The fuel gauge will display a filtered fuel level value. This filter will keep the pointer from moving suddenly or erratically.
• 255=open send +/-0
• 232=Full stop +/-10
• 215=Full mark +/-10
• 178=3/4 mark +/-8
• 138=1/2 mark +/-7
• 93=1/4 mark +/-5
• 41=E mark +/-4
• 54="LOW FUEL" (0-59)
• 0-18=short (0-20 max.)

OIL Displays the code (0-255) for the oil pressure switch input to the instrument cluster. Displays the oil pressure reading 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 (less than 6 psi) or an inoperative engine oil pressure switch will display a value greater than 176.

dEGC Display of engine temperature in Degrees C input from cylinder head temperature sensor. If the value displayed is -40C, the SCP message for engine temperature has not been received for more than 5 seconds.
• 49 C="C" mark
• 60 C=Normal band start
• 120 C=Normal band end
• 119 C=Temperature warning indicator ON
• "-40" C=No SCP Message for 5 sec

br Displays the brake fluid level input to the instrument cluster.

bAtt Displays the code (0-255) battery voltage input to the instrument cluster. Battery voltage gauge will indicate present battery voltage.
• 93-102=6.9-9.1 volts (low voltage)
• 115-124=8.5-10.7 volts (norm band start)
• 215-225=15.8-18 volts (norm band end)
• 230-241=16.9-19.1 volts (high voltage)
rhEo Displays the present hexadecimal value for the instrument cluster backlighting pulse width modulated (PWM) input to the instrument cluster (used when requesting assistance from the hotline).

rhi

rhS

rho PWM input duty cycle.

SCP hexadecimal dimming step (used when requesting assistance from the hotline).
Output driver counts in hexadecimal format (used when requesting assistance from the hotline).

Cr Displays the present RUN/START sense input. Display will show -L with the ignition switch in the START position and -h with the ignition switch in the RUN position.

PA-PE7 Not used.

GAGE Repeats test display cycle.

Turn the ignition switch to the OFF position or press and hold the SELECT/RESET button for three or more seconds and release to exit Instrument Cluster Dealer Test Mode. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.

Instrument Cluster Diagnostic Trouble Code (DTC) Index
DTC Description
B1202 Fuel Sender Open
B1204 Fuel Sender Short to Ground
B1342 ECU is Defective
B2143 Odometer NVM Memory Failure
C1284 Oil Pressure Switch Failure
P1197 SELECT/RESET Switch Circuit Failure
U1027 SCP (J1850) Invalid or Missing Data for Engine RPM
U1041 SCP (J1850) Invalid or Missing Data for Vehicle Speed
U1073 SCP (J1850) Invalid or Missing Data for Engine Coolant
U1123 SCP (J1850) Invalid or Missing Data for Odometer
U1131 SCP (J1850) Invalid or Missing Data for Fuel System
U1132 SCP (J1850) Invalid or Missing Data for Odometer


GEM/CTM Diagnostic Trouble Code (DTC) Index
DTC Description
B1323 Door Ajar Lamp Circuit Failure
B1325 Door Ajar Lamp Circuit Short to Battery
B1342 ECU Is Defective
B1426 Lamp Safety Belt Circuit Short to Battery
B1428 Lamp Safety Belt Circuit Failure
P1804 Transmission 4-Wheel Drive High Indicator Circuit Failure
P1806 Transmission 4-Wheel Drive High Indicator Short Circuit to Battery