Pinpoint Test N: DTC B1676
Climate Control System
Pinpoint Tests
Pinpoint Test N: DTC B1676
Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. Diagrams By Number
NOTE: Before beginning this test, make sure the battery is properly charged.
Normal Operation
Under normal operation, the HVAC receives ground through circuit GD138 (BK/WH). The HVAC module is supplied constant battery voltage through circuit SBP15 (WH/RD) and ignition 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 N: DTC B1676
-------------------------------------------------
N1 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 N2.
-------------------------------------------------
N2 CHECK BATTERY CONDITION
- Refer to Battery, Mounting and Cables Testing and Inspection 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 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 N3.
No
INSTALL a new battery. CLEAR all CMDTCs. TEST the system for normal operation.
-------------------------------------------------
N3 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 N4.
No
REFER to Charging System Testing and Inspection to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation.
-------------------------------------------------
N4 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 N5.
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 N7.
-------------------------------------------------
N5 CHECK CIRCUIT GD138 (BK/WH) FOR EXCESSIVE RESISTANCE
- Ignition OFF.
- Disconnect: HVAC C2357A.
- Measure the resistance between HVAC C2357A-23, circuit GD138 (BK/WH), harness side and ground.
- Is the resistance less than 1 ohm?
Yes
GO to N6.
No
REPAIR circuit GD138 (BK/WH) for an open. TEST the system for normal operation.
-------------------------------------------------
N6 CHECK CIRCUITS SBP15 (WH/RD) AND CBP37 (WH) FOR AN OPEN
- Ignition ON.
- With the engine running, measure the voltage between ground and:
- HVAC module C2357A-13, circuit SBP15 (WH/RD), harness side.
- HVAC module C2357A-12, circuit CBP37 (WH), harness side.
- Are the voltages greater than 10 volts and less than 16 volts?
Yes
GO to N7.
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, VERIFY Smart Junction Box (SJB) fuses 15 (10A) and 37 (10A) are 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.
-------------------------------------------------
N7 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.
- Does the DTC return?
Yes
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.
-------------------------------------------------