What this code means
P0507 may mean the PCM is seeing idle speed higher than the target idle it is trying to control.
What the vehicle may do
- The vehicle may have a high idle.
- The idle may hang or feel slower to come down than expected.
- The check engine light can come on.
Possible fault areas
- Possible extra air entering the engine through a PCV or vacuum leak concern.
- Possible throttle body operation or throttle body wiring and connector concern.
- Possible connector or terminal condition in related circuits.
- Possible ABS communication or data concern affecting vehicle speed information used by the PCM.
Diagnostic path
Opening and code logic
On this Ram 1500 with the 3.6 Pentastar, P0507 means the PCM is seeing idle speed higher than it expects. In plain terms, the module is trying to control idle, but actual engine speed may be staying above the target. The driver may notice a high idle, an idle that hangs, or just a check engine light. Broadly, this can involve extra air getting into the engine, PCV system issues, throttle body control problems, connector problems, or possible ABS communication data affecting how the PCM interprets vehicle speed. The monitor is a commanded-versus-actual idle check: the PCM compares actual engine speed to target idle speed. The monitor runs at idle with no throttle input and vehicle speed at zero after engine run time of more than 30.0 seconds. The code sets when engine speed is more than 200 rpm above idle speed for 30.0 seconds. The MIL will illuminate.
Start with basic checks and confirm the code
Start with the basic system checks before getting into the P0507 path. Then use the scan tool to read codes in all ECUs and record the DTCs and environmental data on the repair order. Save the vehicle scan report and the related recorded data for comparison. After that, erase the DTCs, turn the ignition off for a minimum of 10.0 seconds, turn the ignition back on, and operate the vehicle under the conditions that set the code. Read the DTCs again. If P0507 comes back, continue with this diagnostic path. If it does not come back, treat it as an intermittent condition rather than guessing at parts.
Check for context codes first
Before chasing air leaks or the throttle body, look at the recorded codes. If there are active or pending throttle body faults, or ABS module faults, handle those first. This matters because loss of communication with the ABS module, or implausible ABS data, can make the PCM default vehicle speed to zero while driving. That can falsely fail the idle speed rationality check and set this code. If those faults are not present, move on to the PCV inspection.
Inspect the PCV system
With the ignition off, visually inspect the PCV system hoses and tubes. You’re looking for air leaks, cracked or damaged hoses or tubes, poor hose or tube connections, and a PCV valve stuck open. If you find a problem in the PCV system, repair it as necessary, then verify the repair and confirm the code stays gone. If the PCV system checks out, keep moving down the path.
Check for vacuum leaks
Next, start the engine and check for vacuum leaks. While the engine is running, stay out of the direct line of the fan, keep hands away from pulleys, belts, and the fan, and do not wear loose clothing. Inspect for internal leaks, and inspect external components that can create a vacuum leak. That includes areas like vacuum supply lines, the brake booster, purge solenoid, and engine seals. If you find a vacuum leak, repair it as necessary, then verify the repair and confirm P0507 stays gone. If no vacuum leak is found, go to the throttle body check.
Check throttle body operation
Now inspect the throttle body for proper operation. Look for carbon buildup, other restrictions, and a bent throttle plate. Use a straight edge for the throttle plate check. If the throttle plate does not close entirely, it may be bent and needs to be replaced. With the vehicle running, perform a wiggle test on the ETC motor wiring and connections, and listen for the idle to raise or fluctuate. Use the same running-engine safety precautions here: stay clear of the fan, pulleys, and belts, and keep loose clothing away from moving parts. If you find a throttle body problem, or the idle changes during the wiggle test, verify good pin-to-terminal contact at the throttle body and PCM connectors. If no connector problem is found, replace the throttle body assembly. Disconnect the Battery when replacing the throttle body assembly. After installation is complete, use the scan tool and run the Throttle Body Self Learn, then verify the repair and confirm the code stays gone. If no problem is found in this step, move to the related harness and connector inspection.
Check related harness connections and final decision
For the next step, inspect the related harness connections carefully. Disconnect all PCM harness connectors, any related in-line harness connections if equipped, and the related component harness connectors. Inspect the harness connectors, component connectors, and all male and female terminals. Look for improper connector installation, damaged connector locks, corrosion, water intrusion, weather seal damage if equipped, bent terminals, overheating or discoloration from a poor connection, and terminals pushed back into the connector cavity. Also check for spread terminals and verify proper terminal tension. Repair any conditions you find. Then reconnect the PCM connectors, in-line connectors if equipped, and related component connectors. Make sure every connector is fully seated and the locks are fully engaged. Erase the DTCs, test drive or operate the vehicle under the monitored and set conditions, and read the DTCs again. If P0507 returns after that harness and connector work, the diagnostic endpoint is to replace and program the PCM, then verify the repair and confirm the code stays gone. If the code does not return, the wiring or poor connection problem has been repaired. The takeaway is simple: confirm the code, rule out related throttle body or ABS data issues first, then work through unmetered air, throttle body operation, and connector integrity in order. For more diagnostic training, visit stepdiagnostics.com.
Final check
P0507 is often approached by confirming the code, checking related context faults first, then working through air leaks, throttle body behavior, and connection integrity in order.
For more guided automotive diagnostics, visit STEP Diagnostics.
