P2146 — Fuel Injector Group “A” Supply Voltage Circuit/Open #

Note: The code description may vary depending on the manufacturer.

• GM: Fuel Injector Group “A” Supply Voltage Circuit/Open
• Ford: Injector Group “A” Supply Voltage Circuit Malfunction
• Chrysler: Injector Group “A” Electrical Circuit Open
• Nissan: Fuel Injector Group “A” Power Supply Circuit/Open

Summary of code P2146 #

P2146 is a generic powertrain diagnostic trouble code (DTC) that signals an issue with the supply voltage circuit feeding Group “A” fuel injectors. This means the engine control module (ECM) or powertrain control module (PCM) has detected an open or faulty supply voltage in the circuit dedicated to one set of fuel injectors. “Open” indicates a break or interruption in the electrical path, preventing injectors from operating as intended. This malfunction can significantly affect engine performance, fuel economy, and emissions. Understanding this code is crucial, as it points to an electrical problem, not a mechanical injector failure.

Common symptoms for code P2146 #

When P2146 is stored, your vehicle may display a range of symptoms, depending on the severity of the circuit issue and the number of injectors affected. The engine may run roughly, feel underpowered, or misfire. In some cases, starting can be difficult, or the vehicle may enter a “limp” mode to protect itself.

• Check Engine Light illuminated
• Rough idle or unstable engine operation
• Engine misfires (especially on one cylinder bank or group)
• Reduced power or hesitation under acceleration
• Poor fuel economy
• Difficulty starting, or extended cranking
• Possible engine stalling

Probable causes for code P2146 #

The most likely causes of P2146 relate to electrical faults in the injector supply circuit. Problems range from wiring damage to a failed ECM/PCM. Below is an ordered list, starting with the most common issues:

1. Damaged, corroded, or loose wiring/connectors at the injector harness
2. Blown injector circuit fuse or faulty relay
3. Open circuit within the wiring harness (break, chafing, or pinched wires)
4. Faulty or failing fuel injector(s) in Group “A”
5. Defective ECM/PCM (rare but possible, especially after water intrusion or power surges)

Step-by-step diagnosis for code P2146 #

Diagnosing P2146 requires a systematic approach. Skipping steps can lead to misdiagnosis or unnecessary parts replacement. Here’s a proven process:

• Use a scan tool to confirm the presence of P2146 and record any related codes
• Visually inspect the injector harness and connectors for damage, corrosion, or loose pins
• Check for blown fuses and test the injector power relay (if equipped)
• Using a multimeter, test for battery voltage at the injector supply wire with the ignition ON
• Check for continuity and resistance in the supply circuit from the ECM/PCM to the injectors
• Test each injector in Group “A” for proper resistance (spec per OEM manual)
• If all wiring and injectors test good, suspect ECM/PCM malfunction and consult OEM procedures for further testing or replacement

Possible repairs for code P2146 #

Repairs should directly address the root cause identified during diagnosis. Here are typical solutions, each mapped to the issues above:

• Repair or replace damaged, corroded, or loose wiring/connectors in the injector harness
• Replace blown fuses and faulty relays associated with the injector circuit
• Repair open circuits by replacing or splicing wiring as needed
• Replace faulty injectors in Group “A” as specified by OEM diagnostics
• If verified, replace or reprogram the ECM/PCM

Can you drive with code P2146? #

In most cases: driving is NOT recommended with code P2146 present. While the vehicle may still run, performance will be significantly compromised. Prolonged driving can cause further engine damage due to misfires, raw fuel entering the exhaust (potentially damaging the catalytic converter), or even a no-start condition. If you must move the vehicle, keep it to short distances and seek diagnosis and repairs as soon as possible.

Vehicles most commonly affected by code P2146 #

While P2146 is a generic OBD-II code, it’s most often reported in certain manufacturers that use group-based injector wiring. The following vehicles are frequently seen with this code, especially those with V6, V8, or multi-bank engines:

• Chevrolet Silverado, Tahoe, Suburban
• GMC Sierra, Yukon
• Dodge Ram, Durango
• Ford F-150, Expedition
• Nissan Frontier, Titan
• Jeep Grand Cherokee
• Some Toyota and Honda V6 models

Common mistakes & best practices for P2146 #

Mistakes in diagnosing and repairing P2146 often stem from overlooking the basics or jumping to conclusions. Here’s what to watch out for, and some tips to ensure a correct fix:

• Replacing injectors without checking wiring and fuses first
• Assuming the ECM/PCM is faulty before verifying power and ground circuits
• Neglecting to check for related codes (which may point to a shared issue)
• Not using OEM wiring diagrams to trace circuits accurately
• Skipping a visual inspection of harnesses in high-heat or high-vibration areas

Express FAQ for code P2146 #

Q: Can a single faulty injector cause P2146?
A: Unlikely. P2146 points to a supply voltage issue affecting a group, not an individual injector. However, a shorted injector can sometimes disrupt the group circuit.

Q: Is a special scan tool required to diagnose P2146?
A: A standard OBD-II scan tool can read the code, but advanced diagnostics (like checking injector pulse or circuit voltage) require a digital multimeter and, ideally, a scan tool with live data capabilities.