EQP-101 Oxygen Sensor Tester

Additional information

Fast testing and diagnosing of oxygen sensors


This professional grade oxygen sensor tester uses advanced electronic technology to allow technicians to run response time tests on oxygen sensors.

  • Sensor can be tested on or off the vehicle
  • Shows a pass or fail result in a matter of seconds
  • Equipped with LED bar graph to assist interpret tests
  • The cross count result is displayed in real time during tests
  • The rich/lean mode simulates lean or rich fuel conditions to monitor the response of the engine control module (ECM)
  • Advanced connection detection: automatically detects common wire misconnections like ground, heater wires, disconnected test leads, reversed polarity and more, and displays these on the alphanumeric display
  • Provides instant readings and testing capabilities of the output of the sensor
  • Test sensor response time. Diagnoses “lazy” (slow response) sensors, which may not set DTCs, but cause drivability problems
  • Excellent preventive maintenance tool, to diagnose sensors that need to be replaced before they set DTCs or completely fail
  • Rugged electronics make it almost impossible to damage the instrument, even if wrongly connected
  • No software to upgrade
  • Does not require special setups or in depth knowledge to use

Suitable for:

  • 1 to 4 wire oxygen sensors (Heated or unheated)
  • Zirconium and Titanium (1 Volt and 5 Volt systems)
  • 42 V Ready: can also be used in new generation vehicles with mixed or single 42 Volt systems.

Kit includes:

  • EQP-101 Oxygen Sensor Tester
  • Two piercing clips with 6 ft. cables
  • Two piercing clips with 6 ft. cables
  • Protective rubber holster
  • Polypropylene carrying case
  • 1 x 9 Volt alkaline battery
  • User’s handbook

EQP-101 oxygen sensor tester


Length: 260 mm
Width: 200 mm
Height: 70 mm
Weight: 0.8 kg

EQP-101 oxygen sensor tester

Input Range: 0 to 5 Volt
Input Protection: +/- 48 VDC Max, current limited
Indicators: 20 Segment bar graph and 2 digits alphanumeric display
Bargraph Scale: 0 to 1 Volt or 0 to 5 Volt
Cross Count: 0.1 to 10 CPS
Auto Detection: Detects reversed polarity, ground, heater and open connection
Response test: < 100 ms Pass +/- 5 ms
> 100 ms Fail +/- 5 ms
Test Leads: 2 wire piercing alligator clips with insulating boot, and 6.5 ft cables
Power Source: Standard 9-volt alkaline battery (factory included)
Battery Life: Approx. 25 hrs, with low battery indicator and auto power off
  • Internally protected against power surges, overloads and reversed polarity connections.
  • High temperature silicone 16 AWG test wires and rugged piercing clamps.


It only requires the connection of two probe clips to the oxygen sensor wires, and the selection of the oxygen sensor type.

The sensor signal output is shown in real time on the bar graph, while a 2 digit alphanumeric display shows the sensor output cross count per second.

By pressing the ‘Test’ button and performing a snap throttle acceleration of the engine, it tests the response time of the sensor and shows a pass or fail result within seconds.

EQP-101 Full User Manual PDF

Weight 0.8 kg
Dimensions 26 × 20 × 7 cm