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Sensor Read Test Mode


The Sensor Read Test Mode is used to check output signals of certain sensors as received by the computer. Sensor access codes are used in this mode.
1. Enter system into the Actuation Test Mode (ATM), then press and hold the ATM button until the desired sensor access code appears on the display.
2. Place Read/Hold switch in the Hold position. Since sensor access codes are the same as some ATM test codes, the ATM test circuit will turn on before you move the switch to the Hold position.
3. At this time the readout box will display circuit component output as follows:
a. ATM test circuit 91 (ESA Vacuum Transducer): 01, 0-5 inches Hg vacuum to transducer; 02, 5-15 inches Hg vacuum to transducer; 03, 15 inches Hg vacuum or more to transducer.
b. ATM test circuit 92 (Engine Coolant Sensor Circuit): 01, temperature less than 50° F; 02, temperature between 50-100° F; 03, temperature greater than 100° F.
c. ATM test circuit 93 (Fan Coolant Sensor Reading 4-135 Engine): 01, temperature less than 190° F; 02, temperature between 190-230° F; 03, temperature greater than 230° F.
d. ATM test circuit 93 (Charge Temperature Switch Circuit V6-238, 6-225 and V8-318 Engines): 01, engine cold; 03, engine at normal operating temperature.
e. ATM test circuit 96 (Vehicle Distance Sensor Circuit): 01, switch closed; 02, switch open.