P0654 OBD-II Trouble Code: Engine RPM Output Circuit Malfunction

Our certified mechanics come to you · 12-month, 12,000-mile warranty

SCHEDULE P0654 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0654 code

P0654 is a diagnostic trouble code (DTC) for "Engine RPM Output Circuit Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $69.99. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$69.99$20.00
Toyota$69.99$20.00
BMW$69.99$20.00
SCHEDULE P0654 DIAGNOSTIC Get a fair and transparent estimate upfront

Check Engine Light

P0654 code definition

The P0654 code is stored when the PCM detects a voltage reading from the engine RPM output circuit that does not align with the acceptable range as determined by the manufacturer’s specifications.

What the P0654 code means

During operation, the engine speed is monitored by the PCM through several components. One of these is the Engine RPM Output Circuit, which creates a signal through a grounding process that involves a driver (an internal switch). Each driver is monitored by the PCM through a fault line, sending voltage readings to the PCM for comparison to the manufacturer’s specifications. If the voltage is too high or too low compared to what it is supposed to be in the current operation conditions, the PCM will store the P0654 code.

What causes the P0654 code?

The most common cause behind the P0654 code is a defect in the system circuitry, such as loose or corroded wiring, or loose or broken electrical connectors.

Other causes may include:

  • A faulty instrument cluster
  • An open or shorted instrument cluster harness
  • A faulty tachometer
  • A bad crankshaft or camshaft sensor
  • A faulty PCM, in rare cases

What are the symptoms of the P0654 code?

Most of the time, the illuminated Check Engine light will be the only symptom that the vehicle owner will observe; however, an inoperative or erratic tachometer, and possibly a no start condition, can also occur.

How does a mechanic diagnose the P0654 code?

In order to diagnose the P0654 code, the mechanic should begin by verifying the code with an OBD-II scanner. Once the code has been verified, they should perform a visual inspection of all electrical components, such as wiring and connectors. Because faulty electrical components are the most likely cause of this code, a thorough examination is required. After ensuring that any loose, corroded, or broken components are repaired, the code should be cleared from the PCM and the system should be retested.

If the code comes back after this repair, then the mechanic has diagnosed a more complex issue within the engine RPM output circuit or related components. A specialized scanner, such as an Autohex, may be required to pinpoint the exact area causing the problem. The mechanic should continue checking each component for voltage readings, comparing those to the manufacturer’s specifications, until they’ve discovered the component or sensor that is not operating correctly.

Common mistakes when diagnosing the P0654 code

Most often, mechanics report that a faulty tachometer is blamed, when the PCM driver was actually at fault.

How serious is the P0654 code?

If the P0654 code is detected, it represents an issue that should be addressed right away. This code means that the engine speed cannot be correctly monitored, which could eventually lead to larger issues or dangerous driving conditions.

What repairs can fix the P0654 code?

In order to fix the P0654 code, a technician may attempt several types of repairs. These include:

  • Repair any defects in the system circuitry, replacing loose, corroded, or broken electrical components as necessary.
  • Replace a faulty instrument cluster.
  • Repair an open or shorted instrument cluster harness.
  • Replace a faulty tachometer.
  • Replace a bad crankshaft or camshaft sensor.
  • Replace a faulty PCM, in rare cases.

Additional comments for consideration regarding the P0654 code

If the issue is found to be a bad crankshaft or camshaft sensor, and the part must be replaced, most manufacturers recommended replacing both simultaneously. These sensors work best when they wear at the same time.

Need help with a P0654 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.

P0654
trouble codes
Check Engine Light

Fast and easy Check Engine Light is on Inspection service at your home or office.

SCHEDULE P0654 DIAGNOSTIC
Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.5/5

Number of Reviews

4,150

Rating Summary
3,799
173
45
26
107
3,799
173
45
26
107
Abdul

Abdul

8 years of experience
279 reviews
Abdul
8 years of experience
Excellent communications. Corrected problem and explained what he didd.
2001 OLDSMOBILE AURORA - CHECK ENGINE LIGHT IS ON - DECATUR, GEORGIA
Michael

Michael

13 years of experience
403 reviews
Michael
13 years of experience
Michael was on time, and very knowledgeable at what he does. Takes his time to explain the problem with your vehicle.
2007 CHEVROLET TAHOE - CHECK ENGINE LIGHT IS ON - ATLANTA, GEORGIA
Nathan

Nathan

26 years of experience
235 reviews
Nathan
26 years of experience
Nathan did a good job and explained everything .He was friendly and knowledgeable.Will recommend to others.
1999 FORD F-150 - CHECK ENGINE LIGHT IS ON - TULSA, OKLAHOMA
Troy

Troy

37 years of experience
65 reviews
Troy
37 years of experience
Very knowledgeable
2016 FORD F-150 - CHECK ENGINE LIGHT IS ON - GLENDALE, ARIZONA

More related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...

Related questions

Q: Engine stumbles around 3000 RPM.

Hi there. The engine could be stumbling for the coil pack or distributor may not be functioning correctly. As the coil pack or distributor gets old, the parts tend to become weak and is not able to send an electrical...

Q: When I turn on the AC, the malfunction light comes on and the car doesn't accelerate well and starts jerking.

The trouble code stored in the vehicles computer may shed some light on what's going on. Turning on the AC adds an extra load to the engine and the computer picked up some trouble when the data figures changed. Consider...

Q: Random misfire cylinder 123

I'm curious as to what codes are still active. Is it still a misfire code? Several other component failures can cause "misfire" issues - a clogged exhaust gas recirculation valve, a failed diverter valve, even a failed cam phaser. But...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1-800-701-6230 · hi@yourmechanic.com