Error Code P061C is defined as Internal Control Module Engine RPM Performance. This code is a generic trouble code, meaning it applies to all vehicles equipped with the OBD-II system, especially those made since 1996 up to present. It’s particularly common among Chrysler, Dodge, Ford (Powerstroke), Land Rover, Mercedes Benz, Ram (Cummins), etc. Specifications on the definition, troubleshooting, and repairs, of course, vary from one make and model to another.
The job of the Internal Control Module processor is to monitor various controller self-test duties and overall internal control module accountability. The engine torque calculation system input and output signals are subject to a self-test and are constantly monitored by the PCM and other controllers. The TCM (transmission control module), TCSM (traction control module), and other controllers are bound by the interaction with engine torque monitoring system.
When this code is stored, that means the PCM has seen an internal performance error in the engine revolutions per minute (RPM) monitoring system. Other controllers can also detect an internal error in the PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes) with the engine torque monitoring system, which may contribute to the Error Code P061C.
The PCM (and other controllers) monitors the engine RPM through input signals coming from CKP (crankshaft position) sensor and CMP (camshaft position) sensor/s. The desired RPM is programmed into the PCM and other controllers, while the actual RPM is calculated through input data from CKP and CMP sensors, including TPS (throttle position sensor) and other engine and transmission sensors. The desired RPM is then compared with the actual RPM.
These self-tests are automatically initiated when the ignition is turned on, and the PCM receives power. Aside from running internal controller self-tests, CAN also automatically compares signals from each individual module, ensuring controllers are working properly. These tests are performed simultaneously.
If the PCM sees an internal error in the specified RPM and actual RPM (exceeding the maximum allowable threshold), it will store Error Code P061C and trigger the Check Engine light. Depending on the severity of the condition, it may take multiple drive cycles before the Check Engine light lights up.
- Hesitation upon acceleration
- Increase in fuel consumption
- Engine misfire
Other engine misfire codes may also be present.
Common causes for this code include:
- Defective CKP sensor
- Defective CMP sensor
- Programming error or defective PCM
- Open or shorted circuit or connectors in the CAN harness
- Insufficient control ground module
- Open or shorted circuits between CKP sensors, CMP sensors, and PCM
How to Check
This code is quite a challenging problem to diagnose, and many times, it involves reprogramming issues. Thus, without the right tools and reprogramming equipment, it will be impossible to replace a defective controller and complete the repair.
If the ECM/PCM power supply codes are present, then obviously, they don’t need to be rectified before attempting to diagnose this code. Also, if there are codes for CKP sensor, CMP sensor, or TPS, then they must be diagnosed first.
Make sure you follow the step-by-step guide for diagnosis provided by the manufacturer for CKP, CMP, and TPS sensors. An oscilloscope can be helpful when it comes to testing electromagnetic sensors. Failed components must be replaced.
Many preliminary tests can be performed prior to make sure a controller is defective. A diagnostic scanner, DVOM (digital volt/ohmmeter), and reliable vehicle information is needed for diagnosis of this code.
The first step is to connect the scanner to the vehicle diagnostic port and retrieve all stored codes, including their freeze frame data. You need to write down this information, just in case the problem proves to be intermittent. After writing down all pertinent information, clear the codes and then take the vehicle for a test drive to see if the code resets, or if the PCM enters readiness mode. If the PCM does the latter, then you have an intermittent problem, which is more difficult to diagnose, as it means you would have to wait for the problem to develop more before you can successfully diagnose.
If the code resets, however, then continue with your preliminary diagnosis.
When trying to diagnose this code, refer to your information source or TSB (technical service bulletin); looks for signs and symptoms parallel to the stored code. Search for the year, make, model, and engine of your vehicle. If you can find the right TSB, then you may get the best diagnostic information for your problem.
Use vehicle information source to obtain component locations, connector face views, connector pin-out charts, wiring diagram, and diagnostic flow chart related to your vehicle’s error code.
Then, use the DVOM to the test controller power supply fuses and relays. Next, test and replace any blown fuses as necessary. Fuses must be tested with circuit loaded.
If all fuses and relays are running well, check whether the controller related wiring and harness are in order. You may also want to check chassis and engine ground junctions. Again, use your vehicle information source to obtain ground locations as related circuits and test ground integrity using the DVOM.
Then, check the system controllers for any signs of water, heat, or collision damage. Any controller that is damaged, especially by water, is considered defective and must be replaced.
If controller power and ground circuits are intact, then there’s a good chance the controller is defective, or there’s a programming error in the controller. Thus, controller replacement requires reprogramming. In some cases, you may want to get aftermarket reprogrammed controllers. Some vehicles and controllers require on-board reprogramming that may be done only through the dealership or a qualified shop.
How to Fix
Depending on your diagnosis, possible repairs include:
- Replacement of blown fuses
- Replacement of defective CKP sensors
- Replacement of defective CMP sensors
- Replacement and reprogramming of defective controller
Unlike most codes, this code is likely caused by a defective controller or a programming error in the controller.
Test the integrity of the system ground by connecting the negative test lead of DVOM to the ground, and the positive test leads to battery voltage.