Skip the auto shop - Our mechanics make house calls

P2147 OBD-II Trouble Code: Malfunction with the Fuel Injector Group A Supply Voltage Circuit Low

Check Engine Light

P2147 code definition

P2147 is a generic OBD-II diagnostic trouble code indicating a malfunction with the fuel injector group A supply voltage circuit low.

What the P2147 code means

The P2147 code means than the fuel injector group A has a low supply voltage in the circuit. This low voltage is detected by the Engine Control Unit (ECU) and causes the ECU to set the P2147 code. Once the code is set, the Check Engine Light will be visible on the dashboard. With the code, a failsafe mode will be set to prevent damage to the vehicle. This failsafe mode will remain in effect until the voltage comes back into the specified range or when the fault is repaired.

What causes the P2147 code?

Causes of the P2147 code vary greatly, the most common includes:

  • Faulty fuel injector
  • Poor electrical connection
  • Open or short in the fuel injector harness
  • ECU Failure

What are the symptoms of the P2147 code?

Common symptoms are:

  • Check Engine Light seen illuminated on dashboard
  • Vehicle hard to start
  • Engine has poor or erratic acceleration
  • Poor idle

How does a mechanic diagnose the P2147 code?

A mechanic will begin by using a scan tool to check for what codes are located in the ECU including pending and history codes. The codes found along with the freeze frame data will be checked and noted, then cleared. The mechanic will now take the vehicle on a test drive to attempt to duplicate the symptoms. Once the test drive is completed, a visual inspection will be done to look for any obvious signs of damage or faulty wiring. Next, the scan tool will be used to monitor fuel injector operation. A multimeter will be used to check for the proper voltage at the fuel injector groups as well as the fuel injectors individually. Lastly, the ECU will be tested using manufacturer specific testing.

Common mistakes when diagnosing the P2147 code

Mistakes are made when steps are not followed completely or are done in the wrong order. This leads to misdiagnosis and can waste time and money.

How serious is the P2147 code?

The P2147 code should not prevent the vehicle from being driven after the malfunction starts at a safe location. In cases where the vehicle runs very poorly, the car should not be driven until it can be diagnosed and repaired.

What repairs can fix the P2147 code?

Repairs that can fix the P2147 code are:

Additional comments for consideration regarding the P2147 code

An easy way to check if a fuel injector is working is to use a technician’s stethoscope. This will be placed on the injector and the technician will listen for the typical click noise associated with the injector opening and closing. If no noise is present, the fuel injector is not working properly.

Need help with a P2147 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0121 OBD-II Trouble Code: TPS "A" Circuit Range Performance Problem
P0121 code definition Throttle Pedal Position Sensor/Switch (TPS) A Circuit Range Performance Problem What the P0121 code means P0121 is a generic OBD-II code which indicates that the Engine Control...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: Misfire and P0420

Hello - the P0420 and the inconsistent waveform for the post-cat O2 sensor might be related to your failing intake manifold gasket issue. If tiny droplets of coolant are being sucked into the engine - one failure mode for this...

Q: Kia Sporate Engine check light issue and car stalled this morning!

The infamous "loose gas cap code" is P0442. P0434 is an issue with a heated catalytic converter not coming up to temperature quickly enough. It can be caused by the fuel injection being too rich. If you starter is not...

Q: My van was missing and rough idling then I turned it off one day and the next day it starts then dies and some times it won't start

Hello, thanks for writing in about your 2001 Dodge Caravan. For certain, given your mileage and codes for these 2 components, replacing these 2 sensors is the minimum. Cleaning the idle air control valve, throttle body, and PCV valve should...