Error Code P0200 is described as Fuel Injector Circuit Malfunction. This refers to too high or too low voltage or resistance drop at the injectors. This code is similar to P0201, P0202, P0203, P0204, P0205, P0206, P0207 and P0208, and can be seen alongside other engine misfire codes, including lean or rich condition codes.

This is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II tool, especially vehicles made in 1996 up to present. Specifications on the definition, troubleshooting and repair of the error vary from one make or model to another.


Error Code P0200 means the PCM (powertrain control module, also known as ECM or engine control module) has detected a malfunction in the fuel injector circuit. As its name suggest, the fuel injector circuit injects fuel and dictates how much fuel and when to inject it, as determined by the PCM. This error code means the sensor’s performance is out of range for either the voltage or the injector circuit’s resistance. The PCM will trigger the engine’s failsafe mode, preventing further risk of damage. It will remain until the error is fixed or until normal readings come back.

Common Symptoms

Depending on the severity of the condition, symptoms may vary from one vehicle to another. The staple symptom, of course, is the illumination of the Check Engine light. The most common tell-tale sign however, is that the vehicle runs in a poor condition, misfires or not run at all. Also, the vehicle may experience lean or rich engine condition caused by a damaged fuel injector circuit, which also leads to excessive fuel consumption. Some of the most common symptoms of this code include:

  • Engine start and stalls or not start at all
  • Engine misfires at idle or at highway speed
  • Comes with cylinder misfire codes

Possible Causes

The most common causes of this code are:

  • Defective fuel injector
  • Dirt in fuel injector causing clogging
  • Faulty wiring in fuel injector
  • Corroded fuel injector
  • Open or shorted fuel injector
  • Injector having low internal resistance (fuel injector working outside its specifications)
  • Grounded driver circuit
  • Shorted to voltage driver circuit
  • Wiring harness shorting intermittently against components under the hood

How to Check

As with other error codes, diagnosing P0200 require the checking for any codes present along with the freeze frame data associated with each code present. After that, the codes must be cleared in order to perform a road test. The vehicle must be put in the same condition when the code(s) was set.

Then, check the wiring harness and look for signs of damages, especially the fuel injectors. Also, look for any loose connections and broken components.

Using the scan tool, test the operation of the fuel injector and check for signs of irregularities.

Then, check the voltage for each fuel injector.

Next, install noid light test fuel injector operation as needed.

Also, don’t forget to conduct a manufacturer specific PCM test.

How to Fix

Repairs for this error code are pretty easy and straightforward, which are identified through thorough diagnosis. This includes:

  • Replacement of the fuel injector
  • Repair or replacement of any wiring issues (broken, frayed or shorted wires)
  • Repair or replace connection problems
  • Replacement of PCM (rare)

In some cases, mechanics may use several tools to properly diagnose Error Code P0200, including an advanced scan tool, which is needed for testing for proper operation of fuel injectors monitored by the PCM.

Noid light are installed to the fuel injector wiring to aid visual inspection of the injector operation. This light illuminates if the injector is working properly.

This code can definitely cause drivability issues and pose potential safety risks, thus, it should be addressed as soon as possible.