Service Information

Volt

DTC P219A

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P219A: Fuel Trim Cylinder Balance Bank 1

The Fuel Trim Cylinder Balance diagnostic detects a rich or lean cylinder to cylinder air/fuel ratio imbalance. The diagnostic monitors the heated oxygen sensor (HO2S) signal frequency and amplitude characteristics by calculating an accumulated voltage over a predetermined sample period. An imbalance is indicated when multiple samples of the accumulated voltage are consistently higher than the desired value.

Conditions for Running the DTC

•	DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0119, P0122, P0123, P0128, P0201 - P0204, P0222, P0223, P0300, P0301 - P0304, P0442, P0443, P0455, P0458, P0461, P0462, P0463, P16F3, P2101, P2135 are not set.

•	A scan tool device control is not active.

•	The intrusive diagnostics are not active.

•	The engine overspeed protection is not active.

•	The fuel control is in air-fuel Closed Loop status for greater than 1 s.

•	The system voltage is greater than 10.9 V.

•	The engine coolant temperature is greater than -20°C (-4°F).

•	The engine speed is between 1,350-4,800 RPM.

•	The fuel level is greater than 10%.

Conditions for Setting the DTC

Multiple samples of the pre-catalyst HO2S accumulated voltage are consistently greater than the desired value.

Action Taken When the DTC Sets

DTC P219A is a Type A DTC.

Conditions for Clearing the DTC

DTC P219A is a Type A DTC.

Diagnostic Aids

•	The air fuel imbalance diagnostic is very sensitive to heated oxygen sensor (HO2S) design. An aftermarket sensor or an incorrect part number may cause a DTC to set.

•	Monitoring the misfire current counters, or misfire graph, may help to isolate the cylinder that is causing the condition.

•	Certain aftermarket air filters may cause a DTC to set.

•	Certain aftermarket air induction systems or modifications to the air induction system may cause a DTC to set.

•	Certain aftermarket exhaust system components may cause a DTC to set.

Reference Information

Electrical Information Reference

•	Circuit Testing

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

•	Connector Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

Vehicle in Service Mode, observe the scan tool DTC information. Verify there are no other DTCs set.

⇒	If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

Engine running, observe the MAP sensor parameter. The reading should be between 14-110 kPa (2-16 PSI).

⇒	If not within the specified range, refer to DTC P0106 .

Vehicle OFF, verify that none of the conditions listed below exists:

•	Inspect the air induction system for modified, damaged, leaking, or restricted components.

•	Inspect the crankcase ventilation system for improper operation.

•	Inspect the vacuum hoses for splits, kinks, and improper connections.

•	Inspect for vacuum leaks at the inlet manifold, the throttle body, and the fuel injector O-rings.

•	Test for a restricted, damaged, leaking, or modified exhaust system from the catalytic converter forward. Refer to Symptoms - Engine Exhaust .

•	Test the fuel injectors for improper operation. Refer to Fuel Injector Solenoid Coil Test .

•	Test for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

•	Test for excessive fuel in the crankcase due to leaking injectors.

•	Test the ignition system for improper operation. Refer to Electronic Ignition System Diagnosis .

If all the above conditions test normal, test the engine for any mechanical conditions which could alter the flow into the combustion chamber. Refer to Symptoms - Engine Mechanical .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.