P0859 OBD-II Trouble Code: Traction Control Input Signal High

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

SCHEDULE P0859 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0859 code

P0859 is a diagnostic trouble code (DTC) for "Traction Control Input Signal High". 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 $79.99. 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$79.99$20.00
Toyota$79.99$20.00
BMW$79.99$20.00
SCHEDULE P0859 DIAGNOSTIC Get a fair and transparent estimate upfront

Check Engine Light

P0859 code definition

A P0859 trouble code indicates that the vehicle's Powertrain Control Module (PCM) has reported a malfunction relating to the traction control input signal circuit.

What the P0859 code means

The traction control system regulates several aspects of the vehicle's drive system, particularly with regards to engine power and fuel delivery. A P0859 trouble code will be logged on the vehicle's computer if the PCM fails to receive a signal from the traction control system.

What causes the P0859 code?

  • In the vast majority of cases, the P0859 code is caused by a defective traction control switch. The switch itself may be faulty or damaged. Technicians report defective switches in this code instance are often damaged due to liquid contact.

  • Shorted, corroded and damaged wires may also be to blame for a P0859 signal malfunction. Moreover, technicians have cited a corroded sensor connector as a common reason for this trouble code.

What are the symptoms of the P0859 code?

The reported symptoms of a P0859 code vary from purely traction-related concerns to a failure of the transmission system. Traction problems are most commonly reported, particularly if a P0859 code-afflicted car is driven on slippery surfaces. Harsh or failed shifting may also come alongside a P0859 code. The P0859 trouble code and dashboard trouble indicator will both be activated for the sake of highlighting and diagnosing the concern.

How does a mechanic diagnose the P0859 code?

A technician may first diagnose the P0859 code by reading it via an OBD-II code reader. Components related to the traction system (particularly the traction control system's activation switch) should be inspected and tested for signs of fault or malfunction. All wires relating to the traction control system should be inspected thoroughly in order to verify any potential signs of corrosion, damage, wear or disconnection. In the case that there is a possible issue with one of the vehicle's control modules, a specialized scanner (such as an Autohex) may be used in order to pinpoint the source of the problem.

Common mistakes when diagnosing the P0859 code

Although a faulty traction control module is sometimes to blame for a P0859 code, it is often mistakenly replaced when the real problem lies with broken electrical circuitry or a faulty switch.

How serious is the P0859 code?

A P0859 trouble code can result in drivability issues for the vehicle. Particularly if the vehicle's typical driving surfaces are slippery, a P0859 code can make the vehicle more dangerous to drive. In addition, an unpredictable transmission system resulting from a P0859 can make driving the vehicle a precarious situation.

What repairs can fix the P0859 code?

Additional comments for consideration regarding the P0859 code

The P0859 trouble code only applies to vehicles with electronic traction control systems. Due to the high amount of circuitry associated with this code and the traction system, it is recommended that these repairs be left to a proper technical specialist.

Need help with a P0859 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
Check Engine Light
P0859

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

SCHEDULE P0859 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

4.8/5

Number of Reviews

4,255

Rating Summary
3,898
174
45
26
112
3,898
174
45
26
112
Ben

Ben

39 years of experience
1020 reviews
Ben
39 years of experience
Lexus LS430 - Check Engine Light is on - Houston, Texas
I was very pleased with the courtesy and work of Mr. Smith. He was exceptional in explaining and correcting the problem and thereby gained my trustI . I request he be my mechanic in all future service requests. I had a great experience working with Mr. Ben Smith.
Richard

Richard

19 years of experience
203 reviews
Richard
19 years of experience
Ram ProMaster 1500 - Check Engine Light is on - Bonita Springs, Florida
Prompt, polite and personal. Took the time to explain the process and his recommendations. 2 thumbs up
Michael

Michael

23 years of experience
37 reviews
Michael
23 years of experience
Ford F-150 - Check Engine Light is on - Federal Way, Washington
Very helpful and explained everything and what needs to be addressed. I feel informed and confident in Mike’s assessment and look forward to him performing services on my vehicle.
Rigoberto

Rigoberto

9 years of experience
650 reviews
Rigoberto
9 years of experience
Honda Civic - Check Engine Light is on - Chicago, Illinois
Rigoberto came on time & quickly diagnosed the problem- rats chewed thru wiring near the battery. He wasn’t able to fix it himself bc of parts, but gave me recommendations on where to go & how to not have the dealership sell me services that are not needed.

More related articles

How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...
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...
Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...

Related questions

Q: Air bag deploying

There have been many cases of defective airbags or systems causing a fault code to be stored in the system computer. If there is a fault code stored, the air bag will not deploy because the system has been shut...

Q: Car hesitating on acceleration.

Thanks for writing in about your Mazda 6. You need to make sure that the mass airflow sensor is not getting contaminated by an oil type air filter. If it is, replace the air filter with clean paper type one...

Q: Car won't start

There are many reasons as to why the car may no start, some of which may be related to various sensors. The most efficient way to approach something like this is often times to have the car's computer scanned using...

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