AutoXray EX-SCAN 5000, User Manual

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A/C - Air Conditioner
ECM - Electronic Control Module
EGR - Exhaust Gas Re-circulation Valve
MAP - Manifold Absolute Pressure
TPS - Throttle Position Sensor
A/C (Enabled / Disabled)
If the ECM is commanding the A/C Clutch to engage, this parameter should
indicate ENABLED, otherwise this parameter should indicate DISABLED.
A/C Clutch (Engaged / Disengaged)
An indication that the ECM has sent a command to engage the air
conditioning clutch after receiving the instrument panel request and
determining that conditions are appropriate for air conditioning operation.
A/C Clutch Relay (On / Off)
The ECM will command more A/C pressure by turning the A/C clutch
relay ON.
A/C Evap Temp (°F) Range: 20° to 90 °
Air conditioning evaporator temperature, used by the ECM to prevent
evaporator freeze-up.
A/C Low Pressure (Detected / Not Detected)
An indication of whether adequate pressure is available to operate the air
conditioning system. When detected the pressure has dropped below a
safe limit and system operation is halted.
A/C Pressure (psi) Range: 25 to 460 psi
An indication of air conditioning pressure from the high pressure side of
the system. On 1988 and newer engines.
A/C Press Fan 2 (On / Off)
When the A/C is active the ECM will command the fan 2 output relay to
energize to compensate for added engine load and the parameter should
indicate ON. Otherwise, the parameter should indicate OFF.
A/C Request (Requested / Not Requested)
An indication that the ECM has received the instrument panel request to
turn on the air conditioning. See A/C Clutch.
Air Divert (On / Off)
An indication of whether air has been diverted to the atmosphere to
protect the catalytic converter at wide open throttle in some engines with
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