P0623 OBD-II Trouble Code: Generator Lamp Control Circuit

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

EXCELLENT RATING ON

Cost of diagnosing the P0623 code

P0623 is a diagnostic trouble code (DTC) for "Generator Lamp Control Circuit". 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 $154.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 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 $154.99 $50.0
Toyota $154.99 $50.0
BMW $164.99 $50.0

*Estimates may vary by market

SCHEDULE P0623 DIAGNOSTIC Get a fair and transparent estimate upfront

P0623 trouble code definition

A P0623 trouble code is related to a vehicle’s engine control unit (ECU) and its connection with the battery’s voltage.

What the P0623 code means

P0623 is an OBD-II generic code for a voltage problem between the ECU and the generator control module that helps a vehicle start properly.

What causes the P0623 code?

There could be a variety of causes for a P0623, but the most common culprits are:

  • Bad battery connection
  • Bad alternator connection
  • Weak or dead battery
  • Bad alternator
  • Bad ECU

What are the symptoms of the P0623 code?

Symptoms can vary for a P0623, and some codes will have no impact on the vehicle. Other symptoms include:

  • Weak starting
  • No starting
  • Weak charging
  • No charging

How does a mechanic diagnose the P0623 code?

Because a P0623 is mostly related to a vehicle’s battery and alternator, your mechanic will first test both to ensure voltage and output are within the manufacturer’s parameters. If they are not, either faulty part will be replaced. If they check out however, your mechanic will then ensure wiring and connectors are in good condition, replacing as necessary.

A good cleaning of battery terminals, wire connections and grounds can also help ensure an intermittent code does not return after it’s cleared.

Common mistakes when diagnosing the P0623 code

Like any generic ECU control circuit code, the cause can difficult to find, so it’s important to start with the easiest first before replacement parts like an alternator, battery or ECU are bought. While this may not save time, it will save money.

How serious is the P0623 code?

A P0623 may cause a vehicle not to start or worse, charge while you’re out driving. How the vehicle drives with this code will determine how severe the problem is.

What repairs can fix the P0623 code?

The most common repairs for a P0623 are as follows:

Additional comments for consideration regarding the P0623 code

P0623s are not very common codes, but if you get one, chances are you’re driving a diesel. Because this code is mostly undocumented, chances are high it will coincidental to a different, more obvious issue, i.e. low battery voltage.

Need help with a P0623 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
P0623

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0623 code.

SCHEDULE P0623 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(8600)

Rating Summary
8017
273
65
46
199
8017
273
65
46
199
 at YourMechanic

Brandon

9 years of experience
133 reviews
Brandon
9 years of experience
Ford Escort L4-2.0L - Check Engine Light is on - Nashville, Tennessee
Brandon showed up ahead of schedule, was very personable and diagnosed my problems. He also scheduled my next appointments which will be with him.
 at YourMechanic

William

23 years of experience
33 reviews
William
23 years of experience
Lexus IS250 V6-2.5L - Check Engine Light is on - Mableton, Georgia
Arrived early which was great. William was courteous, and attentive to the issue. Even though it took several attempts I'm so happy he was determined to fix it and he did!
 at YourMechanic

Dan

40 years of experience
1080 reviews
Dan
40 years of experience
Plymouth Grand Voyager - Check Engine Light is on - Lawrenceville, Georgia
Mr. Dan Barber was quite patient, courteous and quite knowledgeable. From my observation, Mr. Barber appears to be quite professional.
 at YourMechanic

Christopher

9 years of experience
120 reviews
Christopher
9 years of experience
Ford Fiesta L4-1.6L - Check Engine Light is on - Smyrna, Georgia
Chris communicated with us each step of the way up until his arrival. He listened well, was knowledgeable, and was prepared. He took the time to diagnose the problem, explained the what, why and how and provided a solution. I would definitely recommend him and will use him again.


More related articles

P0453 OBD-II Trouble Code: Evaporative Emission Control Pressure Sensor High Input
P0453 code means that a reading from the engine’s evaporative pressure sensor is higher than normal due to fuel tank vapor leaks into the system.
P0915 OBD-II Trouble Code: Gear Shift Position Circuit Range/Performance
P0915 means there is a limitation in the gearshift's ability to cover its full range due to corroded, damaged, disconnected, or broken wiring.
P0662 OBD-II Trouble Code: Intake Manifold Tuning Valve Control Circuit High Bank 1
P0662 means there is a voltage problem with the intake manifold tuning valve due to a faulty manifold or wiring issue.

Related questions

Engine light flashing. Car not getting speed and putting out
The Check Engine Light is flashing to tell you that you should get to a safe stopping point so you do not damage the engine or the catalyst of the car. The Check Engine Light does not tell you what...
My engine light and wrench illuminated, rough idling, when stopped and gas pedal depressed it snatches in gear.
Hello. If the Check Engine Light has come on I would always start with a code check. I would use my scan tool to see what codes are in the system as that would give me a good indication of...
My Check Engine Light is on with a code for the engine control module
Unfortunately, without diagnosing the car using a scanning tool to download any potential trouble codes there is no way to tell what other codes may be causing this light to come on. There many different trouble codes that can also...

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