Engine Air Temperature - Actron CP9087 Service Manual

6) Verify test clips make good contact and do not touch each
HIGH
LOW
7) Set RANGE switch to HIGH.
POWER OFF
RANGE
8) Set FUNCTION switch to OHMS.
VOLTS
OHMS
9) Note TEST light position on tester.
FREQUENCY
FUNCTION
10) On-Car test only: Disconnect test leads and reconnect
11) Heat sensor tip thoroughly.
On-Car test: Start engine and idle at 2000 RPM until upper
radiator hose is hot.
Off-Car test:
– Dip sensor tip into boiling water, OR...
– (metal sensor housing) Heat tip with flame from candle or
– (plastic sensor housing) Heat tip with hair dryer.
12) On-Car test only: Turn ignition key OFF. Disconnect
13) Observe TEST light position for test results.
14) Testing is complete.
Set RANGE switch to POWER OFF and remove all test
leads.

Engine Air TEMPERATURE

other.
Make sure red and green test clips are not touching anything.
If the sensor is good, the light will move downwards as the
sensor heats up.
sensor to vehicle wiring harness.
cigarette lighter OR...
vehicle wiring harness from sensor and reconnect test
leads as before.
• Good Sensor - TEST light moved downwards below original
position. (TEST light may go off if sensor is very hot - this is
OK.) The TEST light will move upwards as the sensor cools
off. Range of TEST light movement varies with sensor type
and temperature change.
• Bad Sensor - TEST light position did not change during test.
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