This refers to the second oxygen sensor on Bank 1. Bank 1 is the same side of the engine that cylinder 1 is on, the very front cylinder on the drivers side. It could need to be replaced, or there could be a short to voltage on the O2 signal circuit, or it could also be that the connector has been corroded, and needs to just be cleaned. I believe this code is the same for all vehicles, not just Toyotas.
Check the temp sensor. The control is not turning on the fan when engine temp requires it, so the most common cause is the sensor.
Yes! For a 2007 Toyota Highlander Hybrid, at least, all it takes is the removal of one relay labelled DRL to deactivate with no ill effects. It's a five-minute job that took me almost a year to discover.
Is the AC turned on?
could be a bad crank sensor, it wont always set a code, ive had a few that dont. if you have a scope or scan tool, manually check that the sensor is good.
Parking pawl in transmission broken?
if you disconnect the o2 sensor cable in the air intake then start the engine you would see the check engine sign turned on in the gauge panel. It is on then the sensor is working if off the the sensor may have problems
Good Chance this is caused by a faulty O2 Sensor. I had the engine light stuck on in my 2002 Montana and replaced rear O2 sensor and it turned it off.
If you car is equip with a idler sensor you might want to replace it.
My 2000 Echo had a similar problem. It turned out to be a bad Mass Air Flow Sensor chip, making the car run to rich, and in turn making the engine light come on.
the fans are operated by means of a series of relays which are turned on or off by the engine computer. the engine coolant temp sensor that sends its signal to the engine computer is what indirectly turns on the fans. if there is no check engine light for a coolant temp. sensor code, the problem lies in the fans themselves, or the relays and related wiring.
The camshaft position sensor is located under the distributor cap and rotor. You'll notice a connector from the wiring harness attached to it. The engine will have to be turned over until the notch on the distributor lines up with the sensor in order to remove it
Engine hot and fan cooling it down?Fan temperature sensor bad and it just thinks engine is hot and needs to be cooled down
check your coolant temperature sensor
ive run into this a few times every time it turned out to be the crank sensor. usually coolant drips on it from a leaky water pump and ruins it.Need more info to help. - Ravman
Repair the problem that turned it on and then clear the code with an OBD2 scanner/code reader
Fixed it - Turned out to be a bad MAF sensor.
The harmonic balancer on a 1990 Toyota 4 Runner is turned clockwise to loosen it. This is backwards from most bolts to prevent it from being loosened by the rotation of the engine.
Also, consider whether or not you have the AC turned on. Probably either the relay sticking or a bad (or unplugged) engine coolant temperature sensor.
Throttle positioning sensor
Check the integrity of the wiring. Determine if the fan motor is burned out. More likely, the sensor has malfunctioned. Unplug the sensor (engine off) - the fan should come on when the ignition is turned on. If it does, the sensor is bad.
if the code wasnt cleared by either disconnecting the battery or clearing it with a scan tool then it could take awhile. it will turn off eventually. if you just put a sensor in it without proper diagnosis, there is most likely a different problem that turned the light on in the first place, have the computer scanned and diagnose the problem before replacing parts. it will cost less in the long run. the v6 does have an airflow sensor. its called a "mass" airflow sensor. its located in the air cleaner box. (dont replace it unless properly diagnosed!)
It is not supposed to be on when engine is running unless there is a problem.
Make sure the connector to the Coolant Sensor is not corroded. If so replace with a new connector
On my '84 21R engine it turned out to be the coil after much swapping & cussing.
* It could be a faulty check engine light or a light sensor problem . There's probably not a problem with the engine at all just the faulty sensor light problem most likely. * ----------------------------------------------------------------------------------------------------If your check engine light stays on with the engine running , a malfunction with the emission control system has been detected. Have your vehicle scanned for any trouble codes in order to diagnose and repair the problem. ( I had a check engine light come on at 35000 miles - in my case it turned out to be the DPFE sensor )