2007 Nissan Frontier Emission Monitors Not Ready

2007 Nissan Frontier Catalyist Monitor, Oxygen Sensor Monitor, and EVAP Monitor not setting to "Ready."

I unplugged my battery over 2 months ago. Now after I have ran the recommended drive cycle found in my owners manual over 10 times and put over 2000 miles on my truck the catalyst, oxygen sensor, and the evap monitors are not setting to the ready status. I have a pending OBD2 code P0603 which says Keep Alive Memory Error. Took it to a mechanic and they told me that the aforementioned code is typical when unplugging a battery. My question is, why are those 3 monitors not setting? Is this normal for a 2007 Nissan Frontier?

Answer:

In fact OBDII Trouble Code P0603 does indicate a Keep Alive Memory Error, and with this error your Nissan Frontier will not begin (or complete) setting the required emission monitors in order to pass the smog check.

Possible faults which could cause a P0603 Trouble Code to set include:

- Loose or poor battery terminal connection
- Low battery charge
- ECM power supply (+) circuit is open or shorted
- ECM Programming Error (requires reprogramming)
- Faulty ECM (engine contorl module)

Symptoms of a OBDII Trouble Code P0603 DTC may include an illuminated MIL (malfunction indicator lamp), engine stall, ECM communication trouble codes, no start conditions, and/or failure to complete emission monitors.

P0603 can be a difficult fault to repair and will require diagnosis by a certified smog check repair station or a Nissan dealer service department.

posted by SmogTips Support