Q: Code P0051 shows up on my 03 Nissan Frontier SE crew cab. I have replaced all plug wires, plugs, rotor, cap, cabin filter, air fi

asked by on April 04, 2017

P0051 code keeps showing up as: generic H02S Heater Control Circuit Low (Bank 2, Sensor1) I have changed all plug wires, plugs, air cleaner, cabin filter, checked MAS electrical and cleaned with proper cleaner, new rotor, new cap, new OEM gas cap, changed oil, changed trans fluid and filter and all 4 oxy/sensor (aftermarket) and still keep getting above code even after clearing it several times. Nissan Frontier crew cab SE 2003 117K miles 6cyl gas natural aspirated

My car has 117000 miles.
My car has an automatic transmission.

Oxygen sensors do not work until they reach a certain temperature. The electric heating element helps the sensor come up to temperature faster so that the engine can go into closed loop operation more quickly. P0051 says that there is no voltage at the sensor heater so the engine will take a few more moments to go into closed loop operation. You probably will not notice any symptoms other than the check engine light. Replacing the O2 sensor will often solve this problem, but if the issue is upstream, say in the wiring harness or the heater relay (another common failure) changing the sensor will not help. If you have changed the sensor and still get the code, you will have to do a point to point check of the wiring harness to see where the interruption of power is located. You can have a professional do this for you at your convenience by contacting Your Mechanic. They can send a technician to your home or office to check out your Nissan and let you know just what it;s going to take to solve your problem.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Where are the supplemental restraint system warning labels located?

Your Altima includes two supplemental restraint system (SRS) warning labels. You’ll find one on the outside of the driver side sun visor, and another on the outside of the passenger side sun visor. These warning labels provide important safety...

My Check Engine Light came on. I fixed the issue, but the light quickly came back on. Will it turn itself off?

Just because a code is displayed does not mean that part is bad in all cases. The code is used as a tool to diagnose the problem. You may have to have the code diagnosed by an experienced mechanic like...

My 2003 Lincoln Ls is shaking I was told its my coils and that there is 8 of them they want to charge me almost 600.00 seems awfu

Shaking or vibration may be caused by many different things such as faulty spark plugs, poor fuel pressure or misfires. Other things such as a faulty idle air control valve may cause the engine idle to drop below the normal...

Related articles

A Buyer’s Guide to the 2012 Nissan Frontier
When When looking for a truck, the 2012 Nissan Frontier could be the vehicle you’ve been hunting for. It has a great look, a strong engine, and it is reliable. The vehicle has been making gains on other trucks in...
The Best Used Cars to Buy If You're a Gardener or Landscape Architect
Gardeners Gardeners and landscape architects need to haul around quite a bit of gear. As a gardener, chances are you will need to transport a variety of mowing equipment, along with smaller implements. You may also need to move shrubs,...
The Best Used Cars to Buy If You Live in the Country
Living Living in the country is a whole different way of living. You deal with rough and uneven roads, mud, snow, rain, and ice and you need a vehicle that can stand up to these kinds of conditions with ease....