OEM Ecu Reflash TPS calibration
Service Procedure
OEM ECU Reflash · TPS Calibration
Validating throttle position sensor to factory specifications
Time
35 min
Target
TP% = 7.8
Procedure Overview
Why This Method
In some rare occasions it will be necessary to validate the calibration of the bike's TPS sensor to ensure exact factory specifications. We've found the most accurate way to calibrate the TPS is by reading the live data on a scan tool as opposed to traditional methods that use a meter to read the voltage from the sensor.
Setup
Time to Complete & Equipment Needed
Time to complete
35
minutes
Equipment needed
- Low cost automotive code reader / scan tool
- OBD2 to Euro 5 CAN bus connector cord with flying power lead
Procedure Description
Calibration Steps
- Ensure that the battery on the bike is at least 12.6V
- Connect the scan tool / CAN bus cable to the bike
- Connect the flying lead to the battery + terminal so that the ECU is powered up with the engine off
- If your CAN bus cord lacks the battery connection flying lead, you can provide power to the ECU by carefully backprobing power on the orange wire of the CAN bus data link connector. See photos below.
- Toggle through the display options on the code reader to the live data fields
- Pinpoint the TP % data field
- On the right side of the throttle body, confirm that the yellow fast idle speed knob is pulled out, and while observing the TP % turn the knob counter clockwise to ensure that the number does not change. If it does, continue turning the yellow knob counter clockwise until the number stops descending. The goal of this step is to ensure that the yellow fast idle knob has no influence on the throttle plate.
- On the right side of the throttle body, turn the red idle speed knob counter clockwise while monitoring the number, which should fall as the dial is being turned out.
- Continue turning the red knob until the number stops falling. This indicates that the throttle plate has reached the 100% fully closed position.
- The TP % value should read 7.8 which is the value confirming the TPS sensor is calibrated to the fully closed position.
- If the value reads anything different, loosen the securing screws on the TPS sensor and adjust it until that value is displayed.
- Snap the throttle a few times and re-read the value, which should not change from 7.8
- Once this is confirmed, turn the red knob in clockwise until the TP % value reaches 11.0, which will be a typical value to start the bike.
- Re-install and secure anything removed for the calibration procedure, and using the scan tool, scroll to the ENGINE RPM field and set the idle speed on a hot engine to the values shown below.
- Calibrate the yellow fast idle speed knob by pushing it in and turning it clockwise until the idle speed is raised 500 rpm over the standard idle speed. Pull the knob out to ensure the idle speed drops back down to the previous setting.
Scan tools and CAN bus cables can be purchased from TacoMoto
Shop Tools →
Engine RPM Settings · Hot Idle
Target Idle Speed by Model Family
| Model family | Idle RPM |
|---|---|
| 450 / 500 / 501 EXC-F · XCF-W · FE · FEs | 1,800 – 1,900 |
| 250 / 350 EXC-F · XCF-W · FE · FEs | 1,950 – 2,050 |
| 250 / 350 / 450 SXF · XCF · SM | 2,250 – 2,350 |
Scan Tool Screen Navigation
Finding the TP% Field
The data fields we need are located in the DIAGNOSTIC / LIVE DATA area of the menu. Spend a few moments with your tool to find and locate those screens, then scroll to the TP % value field. Note that the value will change as you open and close the throttle. Your TP % value will likely be in the 11–12% range and will go up as you open the throttle.
Reference Photos
Visual Reference
Reference photos for cable identification, scan tool screens, backprobe technique, and full setup.
FIG 1OBD2 → CAN bus cable with yellow flying power lead
FIG 2Scan tool live data — TP% reading 7.8 (fully closed target)
FIG 3Live data screen — TP% at 11.4% (typical start value)
FIG 4Backprobing the orange power wire on CAN bus connector
FIG 5Full setup — scan tool powered via flying lead to battery