Pinpoint Test Y: DTC B1676
Climate Control System
Pinpoint Tests
Pinpoint Test Y: DTC B1676
Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. Diagrams By Number
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, the HVAC module receives a ground through circuit GD133 (BK). The HVAC module is supplied constant voltage through circuit SBP15 (WH/RD) and switched voltage through circuit CBP37 (WH).
- DTC B1676 (Battery Voltage Out of Range) - The module senses when voltage is less than 9 volts or greater than 16 volts.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- HVAC module
PINPOINT TEST Y: DTC B1676
NOTE: Before beginning this test, make sure the battery is properly charged.
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Y1 RETRIEVE ALL CMDTCs IN ALL MODULES
- Enter the following diagnostic mode on the scan tool: Self Test - All CMDTCs .
- Is DTC B1317, B1318 or B1676 present in more than one module AND DTC P0563, P0620, P0625, P0626 or P065B present in the PCM?
Yes
REFER to Charging System Testing and Inspection for diagnosis of the battery and charging system. CLEAR all Continuous Memory Diagnostic Trouble Codes (CMDTCs). TEST the system for normal operation.
No
GO to Y2.
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Y2 CHECK BATTERY CONDITION
- Carry out the Battery - Condition Test Pinpoint Tests to determine if the battery can hold a charge and is OK for use. Refer to Battery, Mounting and Cables Testing and Inspection.
- Does the battery pass the condition test?
Yes
If the battery passed the condition test but required a recharge, REFER to Charging System Testing and Inspection to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation. If the battery passed the condition test and did not require a recharge, GO to Y3.
No
INSTALL a new battery. CLEAR all CMDTCs. TEST the system for normal operation.
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Y3 CHECK CHARGING SYSTEM VOLTAGE
NOTE: Do not allow the engine speed to increase above 2,000 rpm while performing this step or the generator may self excite and result in default charging system output voltage. If engine speed goes above 2,000 rpm, shut the vehicle OFF and restart the engine before performing this step.
- Measure the voltage of the battery with and without a load on the charging system as follows:
- Turn off all accessories and run the engine at 1,500 rpm for a minimum of 2 minutes while measuring battery voltage.
- Turn on headlights and HVAC fan on high and run engine at 1,500 rpm for a minimum of 2 minutes while measuring battery voltage.
- Are the voltages between 13 and 15.2 volts?
Yes
GO to Y4.
No
REFER to Charging System Testing and Inspection to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation.
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Y4 CHECK FOR VOLTAGE MONITORING THE MODULE SUPPLY VOLTAGE (VBAT_CC) HVAC PID
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: VBAT_CC HVAC PID .
- Monitor the battery voltage VBAT_CC HVAC PID.
- Is the battery voltage less than 9 or greater than 15.5 volts?
Yes
If voltage is less than 9 volts, GO to Y5.
If voltage is greater than 15.5 volts, INSTALL a new HVAC module. REFER to Climate Control Heating Ventilation Air Conditioning (HVAC) Module. CLEAR all CMDTCs. REPEAT the self-test.
No
GO to Y7.
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Y5 CHECK CIRCUIT GD133 (BK) FOR AN OPEN
- Ignition OFF.
- Disconnect: HVAC Module - Dual Automatic Temperature Control (DATC) C228A or HVAC Module - Electronic Manual Temperature Control (EMTC) C2357A .
- Measure the resistance between EMTC C2357A-23 or HVAC module - DATC C228A-23, circuit GD133 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to Y6.
No
REPAIR circuit GD133 (BK). TEST the system for normal operation.
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Y6 CHECK CIRCUITS SBP15 (WH/RD) AND CBP37 (WH) FOR AN OPEN
- With the engine running, measure the voltage between ground and:
- HVAC module - EMTC C2357A-13 or HVAC module - DATC C228A-13, circuit SBP15 (WH/RD), harness side.
- HVAC module - EMTC C2357A-12 or HVAC module - DATC C228A-12, circuit CBP37 (WH), harness side and ground.
- Is the voltage greater than 10 volts and less than 16 volts?
Yes
GO to Y7.
No
If DTC B1676 is present in multiple modules, REFER to Charging System Testing and Inspection. If DTC B1676 is present only in the HVAC module - EMTC or HVAC module - DATC, VERIFY Smart Junction Box (SJB) fuses 15 (10A) and 37 (10A) is OK. If OK, REPAIR circuit SBP15 (WH/RD) or CBP37 (WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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Y7 CHECK THE HVAC MODULE CONNECTION
- Inspect the module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
For EMTC systems, GO to Pinpoint Test X. Pinpoint Test X: The Auxiliary Temperature, Panel/Floor and Blower Motor Controls Are Inoperative/Do Not Operate Correctly Usin
For DATC systems, INSTALL a new HVAC module. REFER to Climate Control Heating Ventilation Air Conditioning (HVAC) Module. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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