Honda Accord P1122 Trouble Code – Test your TPS
The Honda Accord P1122 OBDII trouble code is to indicate an excessive signal from your TPS. Specifically this Honda Accord P1122 code is for a Throttle Position Sensor Signal Higher Than Expected. Today I’ll be showing you how to resolve this Honda OBDII trouble code in a 1997 Honda Accord with a 2.2 liter SOHC engine in it. Your Honda TPS sensor is nothing more than a potentiometer, and as your throttle opens this sensor reads the positioning of the throttle blade.
The Honda TPS is responsible for reading how far the throttle has opened, and it converts this position into a signal that your Honda ECU recognizes. When the TPS starts to go bad it may send a signal that’s over the limit of what the Honda ECU is expecting. You will be using a multimeter to test the functionality of your throttle position sensor. Your Honda Accord TPS is found near the firewall of your engine bay. It’s mounted to the throttle body of your 2.2 liter Honda engine, and it’s connected by a three pin engine harness.
The three wires behind the Honda Accord throttle position sensor are power, ground and the signal wire. Today I will be showing you how to correct the P1122 OBDII trouble code in a 2001 Honda Accord with the ULEV 2.2 liter engine in it.
In order to conduct our test, you will need a multimeter. This device shows you the DC voltage being sent on the signal wire of your Honda Accord TPS. Because there’s just 3 wires at this throttle position sensor, it’s easy to measure the signal voltage being sent to your ECU.
To begin you will need to remove your intake piping. This is done by loosening the worm clamps around the throttle body inlet for your 2.2 liter engine. Next you must remove the hard metal line that connects your positive crankcase ventilation (PCV). Then you will need to slide the intake piping off your throttle body, which will allow you to see the intake inlet.
As shown in the image above, you can manually turn and open your throttle body. This allows you to measure the signal wire easily. The position as shown above is how you will be testing and measuring your Accord TPS signal.
How to fix Honda Accord P1122 trouble code
Because the Honda Accord P1122 trouble code has to relate to the voltage being too high, we will be measuring the sensor output directly. This can be done without starting the engine. All you require is a multimeter to test this sensor properly. First insert your Accord ignition key and turn the ignition to the “ON” position or position II. This sends power to all the engine sensors.
Next you will be measuring the middle pin, but this must be done with the throttle position sensor connected. To do this you must either pierce the signal wire with the TPS connected, or backpin the wire. The signal wire is the middle one, or PIN B as shown below.
This wire is a BLACK wire with a red stripe in it. Now reconnect the sensor as shown above, and measure the voltage with the ignition turned to ON. This wire should measure between .8-1.1 volts with the throttle plate closed. Open the throttle body to the fully opened position as shown below.
The wire should now read between 4.4 – 4.9 volts at wide open throttle, or the throttle blade in the fully open position. If your Accord TPS is reading higher, this is a sign that the internal mechanism has broken or the sensor has gone bad. Anything over this voltage range means that your throttle position sensor must be replaced.
After you replace your throttle sensor, you must calibrate it using this same method to make sure that your Honda computer is getting the right voltage. Have any questions about this guide? Let me know below!