Pinpoint Test V: Insufficient Heat In Auto Start-Stop Mode Only
- Refer to Wiring Diagrams MANUAL CLIMATE CONTROL SYSTEM
for schematic and connector information.
Normal Operation and Fault Conditions
Cabin Heater Coolant Pump, REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P2600:00 Coolant Pump "A" Control Circuit/Open: No Sub Type Information This DTC sets when the PCM senses an open on the cabin heater coolant pump circuits. PCM P2601:00 Coolant Pump "A" Control Circuit Performance/Stuck Off: No Sub Type Information This DTC sets when the PCM senses any of the following conditions:
Dry-Run leads to cabin heater coolant pump running without resistance
Over Temperature
Over/Under Voltage
Impeller Stall
Impeller Speed below minimum speed
Internal ErrorPCM P2602:00 Coolant Pump "A" Control Circuit Low: No Sub Type Information This DTC sets when the PCM senses low voltage on the PWM circuit when commanding it high, indicating a short to ground to the cabin heater coolant pump. PCM P2603:00 Coolant Pump "A" Control Circuit High: No Sub Type Information This DTC sets when the PCM senses low voltage on the PWM circuit when commanding it high, indicating an open circuit to the cabin heater coolant pump. Possible Sources
- Wiring, terminals or connectors
- Low coolant or air in the coolant system
- Cabin heater coolant pump
- PCM
Visual Inspection and Pre-checks
- Inspect for loose or corroded PCM and A/C compressor connections.
- Make sure BJB fuse 69 (15A) is OK.
- NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- V1 CHECK THE CABIN HEATER COOLANT PUMPNOTE: The engine must be auto-stopped to request the cabin heater coolant pump on. Further information can be found in the Owner's Literature for full Auto Start-Stop enabling/disabling.
- Start the vehicle and allow engine to reach normal operating temperatures.
- Using the HVAC controls, select panel mode, set temperature to full hot and set blower speed to low.
- Drive the vehicle above 3 mph (4 km/h).
- Stop the vehicle on a level surface.
- Make sure that the steering wheel is set to the straight ahead position.
- Keep the transmission selector lever in position D, brake pedal pressed and doors closed.
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the PCM coolant pump status (COOLPMP_A_STAT) PID for at least 1 minute.
Does the cabin heater coolant pump turn on?
Yes GO to V6 No GO to V2 - V2 CHECK THE CABIN HEATER COOLANT PUMP CIRCUITS FOR A SHORT TO VOLTAGE
- Disconnect BJB fuse 69 (15A).
- Disconnect PCM C1235B (1.5L) or C1915B (2.0L).
- Disconnect Cabin heater coolant pump C163.
- Ignition ON.
Is there any voltage present?
Yes REPAIR the circuit. No GO to V3 - V3 CHECK THE CABIN HEATER COOLANT PUMP CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
Are the resistances greater than 10, 000 ohms?
Yes GO to V4 No REPAIR the circuit. - V4 CHECK THE CABIN HEATER COOLANT PUMP CIRCUITS FOR AN OPEN
- Disconnect BJB C1035B.
- Measure:
Positive Lead Measurement / Action Negative Lead C163-1 Ground Positive Lead Measurement / Action Negative Lead C163-2 C1035B-41 1.5L
Positive Lead Measurement / Action Negative Lead C163-3 C1235B-21 2.0L
Positive Lead Measurement / Action Negative Lead C163-3 C1915B-20
Are the resistances less than 3 ohms?
Yes GO to V5 No REPAIR the circuit. - V5 CHECK THE CABIN HEATER COOLANT PUMP CIRCUITS FOR A SHORT TOGETHER
Is the resistance greater than 10, 000 ohms?
Yes GO to V6 No REPAIR the circuit. - V6 CHECK THE ENGINE COOLANT LEVELNOTE: Allow the engine to cool before checking the engine coolant level.
- Visually inspect the engine coolant level at the degas bottle.
Is the engine coolant level within specifications?
Yes GO to V7 No Refer to the appropriate Engine Cooling System article. - V7 CLEAR ALL PCM (POWERTRAIN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES
- Connect all disconnected connectors.
Make sure they seat and latch correctly .
- Ignition ON.
- Using a diagnostic scan tool, CLEAR all PCM Diagnostic Trouble Codes (DTCs).
-
NOTE: The engine must be auto-stopped to request the cabin heater coolant pump on. Further information can be found in the Owner's Literature for full Auto Start-Stop enabling/disabling.
Start the vehicle and allow engine to reach normal operating temperatures.
- Using the HVAC controls, select panel mode, set temperature to full hot and set blower speed to low.
- Drive the vehicle above 3 mph (4 km/h).
- Stop the vehicle on a level surface.
- Make sure that the steering wheel is set to the straight ahead position.
- Keep the transmission selector lever in position D, brake pedal pressed and doors closed.
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the PCM coolant pump status (COOLPMP_A_STAT) PID for at least 1 minute.
Does the cabin coolant pump turn on?
Yes If the cabin coolant pump runs for 10 seconds on and 10 seconds off, PURGE the air from the coolant system. Refer to the appropriate Engine Cooling System article. If the cabin coolant pump runs normally, the system is operating correctly at this time. The concern may have been caused by pump connections. ADDRESS the root cause of any connector or pin issues. No INSTALL a new cabin heater coolant pump. REFER to the appropriate REMOVAL AND INSTALLATION .TEST the system for normal operation. If the concern is still present, GO to V8 - Connect all disconnected connectors.
- V8 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect the PCM connectors.
- Repair:
- corrosion (replace connector or terminals - clean module pins)
- damaged or bent pins - replace terminals/pins
- pushed-out pins - replace pins as necessary
- Connect the PCM connectors. Make sure they seat and latch correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Refer to PCM GUIDED ROUTINE TESTING No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.