Auto Meter 4375 - Manual (Page 2)

Non-Heated Oxygen Sensors
These sensors rely on the hot exhaust gases to bring them to
operating temperature. This may take several minutes and may even
cool off when engine is idling. These sensors have 1 or 2 wires. On
2 wire sensors, one wire is ground and the other is the signal. Check
with vehicle manufacturer or wiring diagram for your specific vehicle
to learn which wire is the signal.
O
2
Sensor
Signal
O
2
Sensor
Connect
Purple Wire
O
2
Sensor Internal
Ground (No Wire)
Powertrain Control
Module (PCM)
1 Wire Sensor
O
2
Sensor
Signal (High)
O
2
Sensor
Ground (Low)
O
2
Sensor
Connect Purple Wire
Powertrain Control
Module (PCM)
2 Wire Sensor
Oxygen Sensors
All oxygen sensors must be heated to at least 600˚ F before an accurate signal is produced.
Heated Oxygen Sensors
These sensors have an electrical resistance heater built in to them
and will come to operating temperature usually within 1 minute. These
sensors have 3 or 4 wires, check with vehicle manufacturer, or wiring
diagram for your specific vehicle to learn which wire is the signal.
WARNING
Do not connect ohm meter to oxygen sensor, or touch wire to ground or
power. Damage to oxygen sensor will result. If a volt meter is to be used, only
use a high impedance (10 mega ohm or higher) digital multimeter.
NOTe: Do not disconnect wire to the computer.
O
2
Sensor Signal
O
2
Sensor
Connect Purple Wire
O
2
Sensor Internal
Ground (No Wire)
Heater
Ground
Heater
Power
(+12V)
Powertrain Control
Module (PCM)
3 Wire Sensor
O
2
Sensor
Signal (High)
O
2
Sensor
Ground (Low)
O
2
Sensor
Connect Purple
Wire
Heater
Ground
Heater
Power
(+12V)
Powertrain Control
Module (PCM)
4 Wire Sensor
2