P0427 OBD-II Trouble Code: Catalyst Temperature Sensor Low (Bank 1)

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

SCHEDULE P0427 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0427 code

P0427 is a diagnostic trouble code (DTC) for "Catalyst Temperature Sensor Low (Bank 1)". 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 $70.00. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $30.00 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$70.00$30.00
Toyota$70.00$30.00
BMW$70.00$30.00
SCHEDULE P0427 DIAGNOSTIC Get a fair and transparent estimate upfront

check engine light

P0427 code definition

The P0427 code is detected and stored when the PCM (powertrain control module) detects that the catalyst temperature sensor is reading a lower temperature than the acceptable range in engine bank 1.

What the P0427 code means

This code indicates that the catalytic converter is not operating as efficiently as it should. It could mean that there is a problem with the catalytic converter, or there could be an issue with the catalyst temperature sensor.

What causes the P0427 code?

In most cases, when the P0427 code is stored, the cause of the problem has to do with an issue with the catalyst temperature sensor. Thus, the issue could be:

  • A shorted or open connection with the catalyst temperature sensor’s harness
  • A faulty or damaged catalyst temperature sensor
  • A poor electrical connection to the catalyst temperature sensor
  • A faulty or damaged catalytic converter
  • Exhaust leaks before or in the catalytic converter

What are the symptoms of the P0427 code?

In almost all cases, there will be no discernible difference in the way the vehicle operates. The Check Engine light will illuminate, but this will usually be the only indication of a problem.

How does a mechanic diagnose the P0427 code?

Using an OBD-II scanner, the mechanic will determine that the P0427 code has been stored, along with any other codes that may also have been stored. If other related codes have been stored, the mechanic will address those issues first, clear all codes, and then retest the system.

If the P0427 code is stored again, the mechanic will also check to ensure that the catalytic converter is not under warranty, as all catalytic converters with less than 100,000 miles of use have federally mandated warranties. If the catalytic is under warranty, the mechanic will follow the manufacturer’s directions for honoring the warranty. If not, they will do a visual inspection of the catalyst temperature sensor, its harness, and any electrical connections.

If the problem is not with the temperature sensor, the mechanic will check for exhaust leaks or oxygen leaks before the catalytic converter. If these are detected, they will continue with repairing or replacing the catalytic converter.

Common mistakes when diagnosing the P0427 code

The most common problem that arises when diagnosing a P0427 code is failure to thoroughly inspect and diagnose the cause of the code. In many cases, the code will be stored with other related codes. If those codes are left unresolved, they can lead to not only the detection of the P0427 code but also to catalytic converter failure. Simply replacing the catalytic converter without determining the cause of the code can result in repeated failures of any new catalytic converters installed in the vehicle.

How serious is the P0427 code?

Though it will not initially affect the way the vehicle performs, the P0427 code could be a serious problem if it is stored in relation with other codes.

What repairs can fix the P0427 code?

After doing the repairs to correct any related codes, repairs to specifically resolve code P0427 include:

Additional comments for consideration regarding the P0427 code

Though the P0427 code may not have any identifiable symptoms aside from the Check Engine light illuminating, this code should be addressed as soon as possible. When the Check Engine light is on, the vehicle cannot pass OBD-II emissions testing for registration. Furthermore, if other codes have been stored and/or the P0427 code is left unresolved for long enough, catalytic converter failure can occur, resulting in expensive repairs to the vehicle that may be avoidable with proper maintenance and repairs in a timely manner.

Need help with a P0427 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
P0427

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

SCHEDULE P0427 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

3,936

Rating Summary
3,597
169
44
25
101
3,597
169
44
25
101

Kenneth

17 years of experience
374 reviews
Kenneth
17 years of experience
Great guy
2013 VOLKSWAGEN JETTA - CHECK ENGINE LIGHT IS ON - LOS ANGELES, CALIFORNIA

Breck

17 years of experience
355 reviews
Breck
17 years of experience
Friendly and knowledgeable. Great Experience.
2015 FORD FUSION - CHECK ENGINE LIGHT IS ON - KATY, TEXAS

Honorio

16 years of experience
658 reviews
Honorio
16 years of experience
He was very friendly, competent and helpful.
1999 TOYOTA COROLLA - CHECK ENGINE LIGHT IS ON - MOUNTAIN VIEW, CALIFORNIA

James

27 years of experience
373 reviews
James
27 years of experience
Learnt a lot about my car engine from James. Excellent service, Thank you.
2011 HYUNDAI SONATA - CHECK ENGINE LIGHT IS ON - ORLANDO, FLORIDA

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...

Related questions

Q: P0089 code, fuel pressure regulator performance low. Went into limp mode, then next morning no start

After doing a little research on your particular situation, it looks as though this is a fairly common problem with this model of vehicle. I would suggest contacting your local dealership about the situation due to the fact that I...

Q: 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...

Q: Q: Brake problems

Although I'm not there to inspect your Ford Super Duty, it would seem logical to inspect your Electronic Brake Control Module (EBCM). This component reads all of the braking system’s sensors and activates the ABS or traction control system when...

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