WB D1 Digital Wideband AFR Controller Module (DIY Board)

WB D1 Wideband AFR Controller Module (DIY Board)
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NOTE: We can not provide extensive support to this product since it requires fundamental serial port communication and electronics knowledge. 

It comes with ONLY the wideband controller board and a magnet. New D1 is only 1.50” and 0.90” in size (1/5 of a credit card size) and much more cost effective than any other wideband controller in the market today.
It is smaller and more cost effective than other leading brands in the market today. It comes with features such as:
1 – Simple guidelines for an easy installation
2 – Four types of fuel (E85, Diesel, Gasoline, Methanol) and lambda options
3 – Ready to install with WB G1 LED AFR display and to an EMS module
4 – Multiple outputs for digital (to PC), analog (to data logger / EMS), narrowband for simulation and extra switch options
5 – No need a PC or tablet for programming upper/lower limits and other settings
Required Oxygen Sensor: Bosch Wideband Oxygen Sensor (LSU 4.2 Part#17014)


1 - Analog 0-5V Linear
Range is 9-19 AFR 0V = 9 AFR 5V = 19 AFR
Analog output is Megasquirt compatible. See the youtube link.
2 - Digital output (9600 8N1 serial) to connect to a PC. It is inverted TTL
3 - Simulated NB (NarrowBand) output
* The low and high limits for analog and simulated NB (NarrowBand) can be modified using the setup procedure. 

The O2 sensor should be exposed to free air for the first time calibration. Hold the magnet close to D1, you will see display unit counting from 1 to 6.
Hold the magnet until you get to step 6 and release it to complete the calibration. This should take about 10 seconds.

Once it calibrated, display reads 19.0. You can now connect the O2 Sensor onto the exhaust pipe. See the guidelines on the left. 

For the factory settings, disconnect power, hold the switch while turning the power on and wait for 3 blinks. You should re-calibrate after this action.


WB D1 can be connected to oxygen sensor cable (5 cables) and to power as shown in the picture above. It can draw up to 3A momentarily. Normally suggested to use 5A fused system. After the startup, it will use less the 1A average.
Positive power goes to 12V switched power source (5A fuse) in your vehicle. Ground cable goes to a grounded source such as battery ground (-) post.
Green digital output is 9600 8N1 serial (single byte ie., 90 = 9.0 AFR) that can be connected to your PC or WB G1 display (sold separate) to monitor readings. 

If you want to connect other devices such as data loggers or AFR gauges, you can use white analog for 0-5V linear (9-19AFR) output. Brown narrowband cable is for simulated NB.


Depending on when you release the magnet on D1, you can modify different settings. Pushing and holding 3 secs will start continuous cycle of 6 menu items.

1 – Set the fuel type (1-Lambda [L], 2-E85 [E], 3-Gasoline [A], 4-Diesel [d], 5-Methanol [n]). Default is Gasoline [A]. See the table for fuel types 

2 – Set NB lower limit
3 – Set NB upper limit
4 – Set Analog lower limit (Default is 9 AFR = 0V)
5 – Set Analog upper limit (Default is 19AFR = 5V)
6 – Calibration (Watch YouTube [widebandapsx] video for details) 

A 0: Power ON
A 1: Sensor ON
14.7 AFR or Stoich: Cruising or on Neutral gear
19 AFR or Max range: On gear and gas pedal is not pushed

WB DOES NOT warrants this product as it is quality checked before it is shipped. Due to the nature of the product, the customer is responsible to have enough expertise on how to connect and operate based on the guidelines provided. NO RETURNS ACCEPTED.
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