P0602 OBD-II Trouble Code: Control Module Programming Error

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0602 code

P0602 is a diagnostic trouble code (DTC) for "Control Module Programming Error". 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 $114.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.0 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 $114.99 $20.0
Toyota $114.99 $20.0
BMW $124.99 $20.0
SCHEDULE P0602 DIAGNOSTIC Get a fair and transparent estimate upfront

P0602 code definition

When the Powertrain Control Module stores a P0602 trouble code, it usually indicates a programming error in one of the control modules, including the transmission control module, the antilock brake control module, the anti-theft module, the body control module, the climate control module, the cruise control module, the fuel injection control module, the instrument panel control module, proximity alert module, the traction control module, and the turbo control module. Additional, related codes include P0601, P0603, P0604, and P0605.

What the P0602 code means

A P0602 trouble code signifies problems with a control module, in addition to a programming error within the one of the control modules. The mechanic should keep in mind that some vehicles require multiple drive cycles, upwards of eight, before the check engine light is lit, though the PCM still stores the code upon first occurrence.

What causes the P0602 code?

A poor electrical connection or defective driver in the PCM are the most likely causes for this code to be stored. Additionally, corroded, damaged, or faulty wiring or connectors within the Control Area Network (CAN) Bus harness or a loose or broken wire or ground strap can also cause this code. A defective CAN Bus is also sometimes to blame.

What are the symptoms of the P0602 code?

Symptoms of a P0602 trouble code include problems driving and shifting, engine stalls, and rough idling. In addition to these symptoms, cars with this stored code also suffer from poor acceleration and a decrease in the vehicle's fuel economy.

How does a mechanic diagnose the P0602 code?

To diagnose a P0602 trouble code, the mechanic needs to complete the following steps while using an appropriate OBD-II scanner and a digital volt/ohmmeter:

  • Inspect all wiring, connectors, and components, looking for any loose connections or damage.
  • Download any freeze frame data and stored trouble codes. This information can come in handy when trying to determine the order in which the trouble codes were stored.
  • The mechanic should clear the code and then test drive the vehicle to see if the code returns.
  • If the code returns, the mechanic should connect a specialized scanner, such as one from Autohex or Tech 2, to try and determine the cause of the code storage more quickly. Otherwise, the diagnostic process can become time consuming and cost prohibitive for the mechanic. The mechanic should test any circuitry while the vehicle is in operation for best results.
  • The mechanic should install some sort of memory saving device or run the risk of having to reprogram the PCM and other control modules if a probe is misplaced.
  • Next, test the continuity and ground with the battery of all associated control modules using the digital volt/ohmmeter, making sure to use an auxiliary ground cable.
  • Using a CAN Bus system wiring diagram, test the continuity between the individual control modules.
  • Finally, clear and test the system to see if the code returns.

Common mistakes when diagnosing the P0602 code

Common mistakes by mechanics when diagnosing a P0602 trouble code include mistaking another code, such as codes dealing with engine misfires, lean exhaust, or the fuel injector, as the cause of the vehicle's problems. This misdiagnosis can lead to an unsuccessful repair and a return of the code. Mechanics can avoid this misdiagnosis by repairing and clearing all trouble codes in the order they were stored on the PCM.

How serious is the P0602 code?

In addition to decreases in vehicle performance, such as acceleration, shifting, and idling, a P0602 trouble code can also affect fuel mileage, making the vehicle less efficient.

What repairs can fix the P0602 code?

Once the mechanic has diagnosed the problem, they should set about repairing the vehicle and trying to clear the P0602 trouble code. This process includes making the following repairs if needed:

  • Replace any faulty or damaged wiring, connectors, or components. The mechanic should also make sure that all connectors are securely connected.
  • After testing the individual control modules, replace any that are faulty.
  • Replace the PCM if the fault lies there.

Need help with a P0602 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.

Check Engine Light
trouble codes
P0602

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0602 code.

SCHEDULE P0602 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(7400)

Rating Summary
6879
249
58
41
173
6879
249
58
41
173
 at YourMechanic

David

13 years of experience
393 reviews
David
13 years of experience
Chevrolet Malibu L4-2.4L - Check Engine Light is on Inspection - Marietta, Georgia
He explained everything to me in detail on what I needed to know about my car. Definitely recommend him for getting the job done.
 at YourMechanic

Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Toyota Camry L4-2.2L - Check Engine Light is on - Las Vegas, Nevada
Raymond did a great job however I was charged for two hours labor and he was only here less than 45 minutes. should I expect this on future appointments with your mechanic ?
 at YourMechanic

Shane

17 years of experience
217 reviews
Shane
17 years of experience
Volkswagen EuroVan V6-2.8L - Check Engine Light is on Inspection - Austin, Texas
Arrived on time. Explained the issues he found and how he will fix it. I have parts on order and will schedule an appointment to have Shane install the parts when they arrive.
 at YourMechanic

Kanstantsin

19 years of experience
51 reviews
Kanstantsin
19 years of experience
Ford F-150 V8-4.6L - Check Engine Light is on Inspection - Littleton, Colorado
Kanstantsin arrived early. Was very courteous and professional. Will highly recommend to anyone. Thank you Kanstantsin.


More related articles

P0905 OBD-II Trouble Code: Gate Select Circuit Range/Performance
P0905 means there is an issue within the gate select circuit range/performance often due too the TCM or the select stroke sensor.
P0246 OBD-II Trouble Code: Turbocharger Wastegate Solenoid High
P0246 code means the solenoid circuit reading does not fall within the recommended specifications due to a damaged solenoid, or faulty wiring.
P0880 OBD-II Trouble Code: Traction Control Module (TCM) Power Input Signal
P0880 means that the TCM communication circuit is not communicating with the PCM due to a malfunction in the activation switch.

Related questions

Engine stopped running while driving and will not start again.
Hey there. As you know, this P0340 code (https://www.yourmechanic.com/article/p0340-obd-ii-trouble-code-camshaft-position-sensor-circuit-malfunction-by-jamahl-walker) indicates the camshaft position sensor (https://www.yourmechanic.com/services/camshaft-position-sensor-replacement) is either faulty or not connected properly. The camshaft position sensor monitors the speed of the camshaft providing the ECU with this information. The ECU...
Flashing CEL
The codes you recorded, P0304 (https://www.yourmechanic.com/article/p0303-obd-ii-trouble-code-cylinder-3-misfire-detected-by-spencer-clayton), P0171 (https://www.yourmechanic.com/article/p0171-obd-ii-trouble-code-system-too-lean-bank-1-by-andrew-quinn), P0301 (https://www.yourmechanic.com/article/p0301-obd-ii-trouble-code-cylinder-1-misfire-detected-by-jamahl-walker), P0300 (https://www.yourmechanic.com/article/p0300-obd-ii-trouble-code-random-multiple-cylinder-misfire-detected-by-jamahl-walker), all pertain to engine misfiring. The flashing of the Check Engine Light (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection) signifies that the misfiring is "active" (ongoing) and consequently you should try to get the...
Check Engine Light is on with the P0451 code
Hi there: Unplugging the fuel tank pressure system would unleash an entirely different set of problems - mainly the truck wouldn't start. This error code typically indicates that the EVAP vent solenoid (https://www.yourmechanic.com/services/evaporation-vent-solenoid-replacement) is damaged or faulty, which creates excess...

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 (855) 347-2779 · hi@yourmechanic.com