If DTC P3075 (Engine Coolant Pump Low Current Performance) is set on a 2019 XT4 equipped with the 2.0L 4-cylinder engine (RPO LSY) or a 2019 Silverado 1500 or Sierra 1500 equipped with the 2.7L 4-cylinder engine (RPO L3B), there may be low coolant in the cooling system or air trapped in the system. Do not replace the Engine Coolant Pump for these conditions. (Fig. 17)
Fig. 17
Diagnostic Tips
To check for any leaks that are present in the cooling system, pressure test the system. Any leaks in the cooling system should be repaired following the appropriate Service Information.
Once any coolant leaks have been repaired, be sure to follow the Cooling System Draining and Filling procedure in the appropriate Service Information to properly fill and bleed the cooling system.
Once the engine is started after the coolant service fill procedure, it’s possible that DTC P3075 may reset until all the air is properly purged from the cooling system. At this point, clear any DTCs and, with the engine at operating temperature, road test the vehicle to completely purge any remaining air from the cooling system.
Once the road test is complete, clear any DTCs and operate the vehicle under the conditions for running DTC P3075 according to the Service Information.
TIP: DTCs P3075 and P3076 (Engine Coolant Pump High Current Performance) can detect coolant flow-based failures.
The intrusive diagnostic test for the DTC will run once per ignition cycle if all running conditions are met. The test will run with the coolant pump at roughly 4,000 rpm for 15 seconds and with the pump motor AC current within the expected range. The coolant pump AC current feedback will be lower if the cooling system is leaking or low on coolant.
Use GDS 2 to confirm that DTC P3075 has ran and passed in the current drive cycle to ensure the diagnostic test has been executed and no fault is detected before releasing the vehicle.
If the vehicle returns with DTC P3075 set, replace the Engine Coolant Pump. Parts will be required to be returned to the Warranty Parts Center.
Refer to #PIP5650A for additional information.
– Thanks to Robert Halas
