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C: Display Does Not Respond To Buttons, No Beep When Button...

Pinpoint Test C - Display Does Not Respond To Buttons Or No Beep When BUTTONS PUSHED OR DRIVER ALERT GIVEN

C1 - Check For Warning Chime

NOTE: Buttons function only with ignition switch in RUN.

- Check for fasten safety belt reminder chime or key in ignition reminder chime.

Does chime sound?

YES GO to C2.
NO REFER to Audible Warning Device for chime diagnosis. Audible Warning Device

C2 - Check Electronic Automatic Temperature Control Metric Mode Output

- Check E/M button operation.

Is electronic automatic temperature control stuck at metric mode?

YES GO to C10.
NO GO to C3.

C3 - Check Electronic Automatic Temperature Control English Mode OUTPUT

- Check E/M button operation.

Is electronic automatic temperature control stuck at English mode?

YES GO to C8.
NO GO to C4.

C4 - Check Switch Wiring Connections

- Remove finish panel to expose instrument cluster.
- Verify that connections at message center switch module assembly are securely connected.

Are connections secure?

YES GO to C5.
NO Secure connections and RECHECK.

C5 - Check Message Center Switch Assembly (No Switch Pressed)

- Disconnect message center module.
- Measure the resistance between pin 5, circuit 143 (LB/Y) and pin 4, circuit 676 (PK/O) of the message center switch module.
- Resistance with no switch pressed should be 17,300 to 17,600 ohms.

Is resistance within range?

YES GO to C6.
NO REPLACE message center switch module. RESTORE vehicle. RETEST system.

C6 - Check Switch Assembly (Buttons Pressed)

- Disconnect message center module from electronic instrument cluster.

NOTE: Press only one button of the message center switch module while pressing the problem button.

- Measure the resistance between pin 5, circuit 143 (LB/Y) and pin 4, circuit 676 (PK/O).

NOTE: Measure resistance between pins 6 and 4 for SELECT forward and REVERSE, between pins 5 and 4 for E/M Reset.

- The resistance should be:

Pins Button Resistance (ohms)
5-4 E/M 5100-5200
6-4 SELECT (forward) 5100-5200
6-4 SELECT (reverse) 2250-2350
5-4 RESET 2250-2350

Is resistance within range?

YES GO to C7.
NO REPLACE message center switch module. RESTORE vehicle. RETEST system.

C7 - Verify Harness Continuity

- Disconnect battery ground cable.
- Remove electronic instrument cluster.
- Check continuity in circuit 143 (LB/Y), connector pin C1-3 and 152 (LB/W), connector pin C2-23.
- Using an ohmmeter, check resistance to ground in circuit 676 (PK/O) and pin 8 of switch module, C1-S of electronic instrument cluster (BK/LB).

Is resistance 10K ohms or less?

YES REPLACE electronic instrument cluster. AFFIX odometer sticker to door pillar. RESTORE vehicle. RETEST system.
NO SERVICE respective circuit. RESTORE vehicle. RETEST system.

C8 - Check EATC Input From Cluster In English Mode

- Turn ignition switch to RUN.
- Remove the connector from the electronic automatic temperature control.
- Press the E/M button so that the instrument cluster is in ENGLISH mode.
- Check electronic automatic temperature control connector pin C2-20, circuit 506 (R).

Is pin 20 at 5 volts DC?

YES REFER to Heating and Air Conditioning for Electronic Automatic Temperature Control Diagnostics. Heating and Air Conditioning
NO GO to C9.

C9 - Check Electronic Instrument Cluster Output To Electronic Automatic Temperature Control In English Mode

- Leave ignition switch at RUN.
- Connector is removed from the electronic automatic temperature control.
- Press the E/M button so that the instrument cluster is in ENGLISH mode.
- Remove connector C2 from instrument cluster. Check pin 32 of the instrument cluster (not the harness connector).

Is instrument cluster pin 32 at 5 volts DC?

YES SERVICE circuit 506 (R) for short to ground or to another wire. RESTORE vehicle. RETEST system.
NO REPLACE electronic instrument cluster. AFFIX odometer sticker to door pillar. RESTORE vehicle. RETEST system.

C10 - Check EATC Input From Electronic Instrument Cluster In Metric Mode

- Turn ignition switch to RUN.
- Remove the connector from the electronic automatic temperature control.
- Press the E/M button so that the instrument cluster is in METRIC mode.
- Check electronic automatic temperature control connector pin C2-20, circuit 506 (R).

Is pin 20 at 0 volts DC?

YES REFER to Heating and Air Conditioning for automatic temperature control diagnostics. Heating and Air Conditioning
NO GO to C11.

C11 - Check Electronic Instrument Cluster Output To Electronic Automatic Temperature Control In Metric Mode

- Leave ignition switch at RUN.
- Connector still removed from the electronic automatic temperature control.
- Press the E/M button so that the instrument cluster is in METRIC mode.
- Remove connector C2 from instrument cluster.
- Check pin 32 of the instrument cluster (not the harness connector).

Is instrument cluster pin 32 at 0 volts DC?

YES SERVICE circuit 506 (R) for open. CHECK for intermittent contact. RESTORE vehicle. RETEST system.
NO REPLACE electronic instrument cluster. AFFIX odometer sticker to door pillar. RESTORE vehicle. RETEST system.