Pinpoint Test G: DTC B1676
Climate Control System
Pinpoint Tests
Pinpoint Test G: DTC B1676
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 - Dual Automatic Temperature Control (DATC) receives a ground through circuit GD145 (BK/BU). The HVAC module - DATC is supplied constant battery voltage through circuit SBP28 (GN/RD) and ignition switched voltage through circuit CBP20 (YE/VT).
- DTC B1676 (Battery Pack Voltage Out Of Range) - The module senses when battery 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 - DATC
PINPOINT TEST G: DTC B1676
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G1 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 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 G2.
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G2 CHECK BATTERY CONDITION
- Refer to Battery and carry out the Battery - Condition Test. Pinpoint Tests
- Does the battery pass the condition test?
Yes
If the battery passed the condition test but required a recharge, REFER to Charging System 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 G3.
No
INSTALL a new battery. CLEAR all CMDTCs. TEST the system for normal operation.
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G3 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 G4.
No
REFER to Charging System to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation.
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G4 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 G5.
If voltage is greater than 15.5 volts, INSTALL a new HVAC module. CLEAR all CMDTCs. REPEAT the self-test.
No
GO to G8.
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G5 CHECK CIRCUIT GD145 (BK/BU) FOR AN OPEN
- Ignition OFF.
- Measure the resistance between ground and HVAC module - DATC C228A-2, circuit GD145 (BK/BU), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to G6.
No
REPAIR circuit GD145 (BK/BU) for an open. TEST the system for normal operation.
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G6 CHECK CIRCUIT SBP28 (GN/RD) FOR AN OPEN
- Ignition OFF.
- Disconnect: HVAC Module - DATC C228A.
- Measure the voltage between ground and HVAC module - DATC C228A-13, circuit SBP28 (GN/RD), harness side.
- Is the voltage greater than 10 volts?
Yes
GO to G7.
No
VERIFY Smart Junction Box (SJB) fuse 28 (10A) is OK. If OK, REPAIR circuit SBP28 (GN/RD) for an open. TEST the system for normal operation.
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G7 CHECK CIRCUIT CBP20 (YE/VT) FOR AN OPEN
- Ignition ON.
- Measure the voltage between ground and HVAC module - DATC C228A-3, circuit CBP20 (YE/VT), harness side.
- Is the voltage greater than 10 volts?
Yes
GO to G8.
No
If DTC B1676 is present in multiple modules, refer to Charging System.
If DTC B1676 is present only in the HVAC module - Electronic Manual Temperature Control (EMTC) or HVAC module - DATC, VERIFY SJB fuse 20 (10A) is OK. If OK, REPAIR circuit SBP28 (GN/RD) for an open. TEST the system for normal operation.
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G8 CHECK THE HVAC MODULE CONNECTION
- Disconnect and inspect the HVAC module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Operate the system.
- Enter the following diagnostic mode on the scan tool: Self-Test - HVAC Module.
- Do the DTCs return?
Yes
INSTALL a new 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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