P0818 OBD-II Trouble Code: Driveline Disconnect Switch Input Circuit

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

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0818 code

P0818 is a diagnostic trouble code (DTC) for "Driveline Disconnect Switch Input 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. 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$20.00
Toyota$20.00
BMW$20.00
SCHEDULE P0818 DIAGNOSTIC Get a fair and transparent estimate upfront

A P0818 trouble code is related to a four wheel drive vehicle’s transfer case and its neutral position switch (driveline disconnect).

What the P0818 code means

P0818 is an OBD-II generic code for a voltage problem with a four wheel drive vehicle’s transfer case neutral position switch. If the engine computer detects a signal from the switch indicating the transfer case is in neutral when the vehicle is in high range or moving, it will indicate a problem with the switch itself, causing a P0818.

What causes the P0818 code?

The most common causes for a P0818 are:

  • Faulty transfer case indicator switch wiring harness and or connector
  • Faulty neutral position switch
  • Faulty wiring or ground from transfer case switch to engine computer
  • Faulty engine computer

What are the symptoms of the P0818 code?

Because a P0818 indicates the transfer case is in neutral when it in fact is not, there should be no noticeable symptoms other than a check engine light. If you encounter this code, it’s wise to ensure your transfer case will shift from high range, neutral, and low range.

How does a mechanic diagnose the P0818 code?

It’s likely your mechanic will first clear the code, reset the engine computer, ensure the transfer case is in a normal position, and test drive to ensure the P0818 comes back. If it does, they will then move on to the switch connector and wiring harness, testing both for proper resistance. If either do not meet the manufacturer’s specifications, they should be replaced. If they do however, there could be an issue with the neutral position switch itself. This should be tested for resistance and replaced as necessary.

While rare, a bad ground or connector between the engine computer and the transfer case wiring harness could cause a P0818, but this won’t be investigated until it’s confirmed both the neutral position switch and wiring harness are in good condition.

Common mistakes when diagnosing the P0818 code

Driver error may cause a P0818 to become a stored code, so it’s wise to first clear the code, reset the ECU, and test drive the vehicle before parts are replaced.

How serious is the P0818 code?

A P0818 by itself shouldn’t cause any mechanical or driveability issues. However, if it is accompanied by other codes, there could be an issue with the transfer case wiring.

What repairs can fix the P0818 code?

The most common repairs for a P0818 are as follows:

  • Replacing the transfer case neutral position switch
  • Replacing damaged wiring and or connectors for the neutral position switch
  • Cleaning bad grounds for the neutral position switch

While rare, replacing the engine computer may be a needed repair as well.

Additional comments for consideration regarding the P0818 code

P0818 codes are common in Toyota SUVs and 4x4s - especially FJ Cruisers and Lexus LX/GX models.

Need help with a P0818 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.

trouble codes
OBD-II
P0818

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0818 code.

SCHEDULE P0818 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.8/5

Number of Reviews

5,064

Rating Summary
4,665
194
48
27
130
4,665
194
48
27
130

Mario

8 years of experience
22 reviews
Mario
8 years of experience
Chrysler PT Cruiser - Check Engine Light is on - Los Angeles, California
He was very courteous and knowledgeable. You can tell he knows his trade. Satisfied with his service.

Yoel

8 years of experience
91 reviews
Yoel
8 years of experience
Nissan Versa Note - Check Engine Light is on - Upper Darby, Pennsylvania
Yoel is very competent and provides great customer service. He took the time to explain and show me exactly what was going with my car. I will definitely use him again and recommend him to others.

Jason

31 years of experience
148 reviews
Jason
31 years of experience
Ford Explorer - Check Engine Light is on - Phoenix, Arizona
Jason was on time, friendly, explained everything he was doing and let me know the other services available, so when Jason comes back to install the new part I am having the oil changed too.

DeVaughn

25 years of experience
1 reviews
DeVaughn
25 years of experience
BMW X3 - Check Engine Light is on - Moreno Valley, California
The mechanic arrived on time, completed the work, which was replacement of an oxygen sensor, in a timely and professional manner.


More related articles

B1538 OBD-II Trouble Code: Memory 2 Switch Circuit Short To Ground
B1538 means there is there is a circuit error with a power-operated seat. This could be caused by a DSM failure or faulty electrical component.
P0286 OBD-II Trouble Code: Cylinder 9 Injector Circuit High
P0286 P0286 code definition When the P0286 code gets stored, it’s because the vehicle’s ECM has received a voltage reading from the fuel injector circuit that isn’t within the parameters designated by the manufacturer. The reading could have also come...
P0072 OBD-II Trouble Code: Ambient Air Temperature Sensor Circuit Low
P0072 P0072 code definition Ambient Air Temperature Sensor Circuit Low Input Depending on the type of vehicle these are some related OBD-II Diagnostic Trouble Codes: P0070: Ambient Air Temperature Sensor Circuit P0071: Ambient Air Temperature Sensor Range/Performance P0073: Ambient...

Related questions

Getting several codes fuel system too lean, Misfire cylinder 3 fuel cut off, misfire detected with low fuel

System too lean means that the fuel mixture has moved beyond the ability of the feedback system to compensate. One thing that can cause that is an air leak that enables air to enter the intake system without passing first...

My car has poor acceleration.

From what you've described, it sounds like you may have a mass airflow sensor that is giving incorrect data for the altitude you are at. This can cause low power, pinging, and O2 codes indicating a too lean condition. A...

AC failed and started running rough and the Check Engine Light came on. But NOW its fine.

I wouldn't concern yourself with the timing of your cars symptoms. When a car fails, I liken it to when a light bulb decides to burn out. It was just its time. Everything will eventually fail. I also would strongly...

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