P062B: Internal Control Module Fuel Injector Control Performance

P062B monitors the injector driver stage inside the engine module. On direct injection engines a separate driver chip generates the boost voltage for opening the injectors and is configured by the main processor via SPI; GM checks initialisation, boost voltage (petrol: 90 V or more or 40 V or less), self-test, data download and communication, and sets the code in the first trip – while it is active, single injector circuit codes are suppressed. Saab's 2.0 L turbo also counts a short to ground in an injector circuit (10 s, two trips). Ford's diesel uses it as a plausibility check of the injection command (post injection, energising over 200 µs during overrun), Ford petrol engines only with cylinder deactivation. Chrysler's 3.0 L EcoDiesel was fixed by software. Misfires, loss of power or stalling follow.

Symptoms

• Check engine light (GM in the first trip)
• Stumbling, misfires, loss of power
• Starting problems or stalling
• Other injector codes are not reported while P062B is active (GM)

Most likely causes

• Short to ground on an injector high-voltage or control wire, or a faulty injector
• Engine module software or calibration fault (update available)
• Undervoltage or supply problem (battery, main relay)
• Faulty driver chip in the engine module

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the connector and wiring of the injector indicated
2. Compare the reading with other engine data while varying the engine speed.
3. Measure the resistance and compare it with the manufacturer's specification
4. Check the control signal with an oscilloscope; on direct injection or diesel engines, leave this to a repair shop because of the high voltages
5. On diesels, check the per-cylinder injection corrections

Good to know

• Repair difficulty: hard
• It can trigger limp mode.
• It affects emissions.

What each character of P062B means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 6: Control modules and outputs
• 2B: Specific fault in that system

Frequently asked questions

Can I keep driving with code P062B?

Drive as little as possible and go to a repair shop. If you smell fuel or the engine is shaking badly, do not keep driving.

What causes code P062B?

The most common causes are: short to ground on an injector high-voltage or control wire, or a faulty injector; engine module software or calibration fault (update available); undervoltage or supply problem (battery, main relay).

Related codes

• P062DFuel Injector Driver Circuit Performance Bank 1
• P0201Cylinder 1 Injector A Circuit/Open
• P0261Cylinder 1 Injector A Circuit Low
• P02EECylinder 1 Injector Circuit Range/Performance
• P0611Fuel Injector Control Module Performance
• P061BInternal Control Module Torque Calculation Performance

Sources

• law.cornell.edu: 13 CCR 1968.2
• gsi.ext.gm.com: 18OBDG03A Engine Diagnostics
• gsi.ext.gm.com: 18OBDG04 Engine Diagnostics
• fordservicecontent.com: obd summary diesel 2023

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.