OBDII trouble code P0340 relates directly with the camshaft position sensor (CPS) in your Scion xB, and today we’ll be showing you how to service your CPS. The specific OBDII verbiage for this error is Camshaft Position Sensor Circuit Malfunction, and it can cause problems with your vehicle starting or running. Today we are working on a 2006 Scion xB with a 1NZFE engine in it, and testing the camshaft position sensor Toyota part number 90919-05024.

Before we get into how to service a Scion xB camshaft position sensor, many people ask us what is the camshaft position sensor and where is my camshaft position sensor? The Toyota camshaft position sensor is no different than any other hall effect style position sensor. The Scion camshaft position sensor is a magnetic hall effect sensor that utilizes an iron core which is wrapped with copper wire to generate a current.

This electrified copper wire uses the camshaft machining to accurately pinpoint where the camshaft and crankshaft are in relation to the engine.  When the crankshaft turns twice, the voltage is generated 3 times in the CMP sensor and translated to a voltage signal. This CPS signal is then used to control ignition timing, and fuel injection timing to operate the engine.

Symptoms of the P0340 DTC OBDII check engine code

1. Car won’t start
2. Car starts and dies immediately
3. Malfunction Indicator Lamp on

Possible Causes

1. Failed CPS sensor circuit
2. Timing chain has jumped one tooth
3. Crankshaft position sensor (CKP) or Camshaft position sensor (CPS) misaligned or misinstalled.
4. Short or break in CPS wiring or ECU circuit

Possible Related codes

1. P0340: Camshaft position sensor range check
2. P0340: Camshaft position/crankshaft position misalignment

How To Service a Scion XB Camshaft Position Sensor

The first step of our how to service a Scion xB camshaft position sensor guide is to locate the CPS sensor on the 1NZFE engine. This sensor is located at the end of the intake camshaft, mounted to the side of the cylinder head by a 10mm bolt.

The first order of business is to test the wiring section of your Scion CPS, locate your crankshaft positon sensor and unplug it. You will first begin by testing your camshaft position sensor to see if it’s good by using a multimeter.

Now taking your multimeter or voltmeter, measure the terminals of the two pin Scion camshaft position sensor for the correct resistance values. You are looking for the operational ranges of 1,630 to 2,740 Ω at room temperature, and 2,065 to 3,225 Ω if the engine is over 120 degrees F.

If your sensor’s resistance values are not within this acceptable range, your camshaft position sensor has failed and will require you to replace it. Removal and replacing the camshaft position sensor is an easy and straightforward process, simply unplug, unbolt and replace. You can clear your check engine light using a scan tool or merely disconnecting your battery.

If your camshaft position sensor checks out however, there may be a bigger issue at hand that’s causing your P0340 DTC trouble code. The next part of our how to service a Scion xB camshaft position sensor is testing the camshaft position sensor harness.

In the diagram above the 1NZFE camshaft position sensor connector wiring is shown as PIN 1 and PIN 2. You are going to be tracing back these wires to your Scion ECU and testing for a short between the connector and ECU. PIN 2 is identified as NE- and PIN 1 on the Scion Camshaft Position Sensor harness is G2+.

Where is the Scion xB ECU?

The ECU for your Scion xB 1NZFE is located behind your glovebox inside the Scion’s cabin. Open your glovebox and undo the clips that hold it up, allowing to sag open fully. The ECU is mounted there behind the glovebox by 10mm bolts, undo these bolts and slide the ECU out towards you.

The part number for this 1NZFE ECU is 89661-52E40, and we’ll be testing from just one of the ECU plugs to diagnose the problems behind your P0340.

The plug shown is the E5 ECU plug, and this plug is the one you’ll be most concerned about when it comes to learning how to service a Scion XB Camshaft Position Sensor. Unplug this ECU connector and refer to the ECU pinout diagram below to test for a break or short in your harness.

To test the wiring portion of your Scion xB, measure the resistance between the G2+ terminal on the E5 connector and the CPS connector. If your multimeter or voltmeter do not have wire leads long enough, extend either the ECU side of the wires or the engine harness side to make the proper readings.

There should be below 1 Ω of resistance on these two wires, signifying that there is no problem with the wiring in your xB. If there is a break or short in your wiring, you will need to replace or cut out the section of damaged wire, try looking for a section of wire that may be exposed or rotting. If this is not a possible fix, then you will need to replace the entire engine harness to resolve your P0340 OBDII Code.

Have any questions on how to service a Scion xB Camshaft Position Sensor? Leave them for us below!