GxT Ferret 91 2-Channel Labscope - Manual (Page 11)

11
Sensor Tests
Optical (CKP/CMP)
Connect COM probe to the sensor’s ground circuit, engine
block, or negative battery post. Connect CH1 probe to
the sensor’s signal circuit to the PCM. Crank or start the
engine. Let the engine idle, rev the engine, or drive the
vehicle to make the driveability or emissions problem
occur. Check the waveform for proper shape, frequency,
and amplitude.
Dual Trace Hall Eff
Connect COM probe to the sensor’s ground circuit, engine
block, or negative battery post. Connect CH1 probe to
the crankshaft sensor’s signal circuit to the PCM. Connect
CH2 probe to the camshaft sensor’s signal circuit to the
PCM. Crank or start the engine. Let the engine idle, rev
engine, or drive the vehicle to make the driveability or
emissions problem occur. Check the waveforms for proper
shape, frequency, and amplitude.
Magnetic CMP
Connect COM probe to the sensors’ “low”, “-”, or ground
circuit. Connect the CH1 probe to the camshaft sensors’
“high”, “+”, or signal output to the PCM or ignition control
unit. Crank or start the engine. Let the engine idle, rev
the engine, or drive the vehicle to make the driveability or
emissions problem occur. Check the waveform for proper
shape, frequency, and amplitude.
Magnetic VSS
Connect COM probe to the sensor “low”, “-” or ground
circuit. Connect CH1 probe to the sensor “high”, “+”, or
signal output to the PCM. As the wheels begin to spin,
symmetrical oscillations should increase in amplitude as
wheel speed increases.