2. CAN high speed bus at 2MS on screen A
4. CAN high speed bus at 4MS
6. CAN high speed bus at 4MS on screen A
8. CAN high speed bus at 40MS
10. Controls & Stacked Scope
12. Setup & Dual Scope A Time Base Only
14. Setup & Meter
2: 740 Volvo Crank Trigger and Coil Signals
4: eSCOPE Feedback with 10 percent
add to MAF
Yellow trace is MAF input to eSCOPE
Purple trace is EScope output to PCM
6: Front and Rear O2 Sensors
8: Honda Coil Feedback at Coil
10: Honda Coil Timing Signals
12. 4.2 Liter Jeep Carburetor Circuit
14. This waveform was taken at the fuel pump relay (power side of fuel pump) with a current clamp after fuel had been added to the empty fuel tank. Note the Freq (Hz) is 79.26 and multiply this by 60 sec. to find the RPM of the fuel pump was 4755.6 RPM.
16. This GM vehicle was still running and came into the shop for an intermittent stalling problem. The vehicle never stalled but the problem was found using an Amp clamp on the power wire to the fuel pump.
20. This shows the front and rear O2 sensor signals. The yellow and red traces are the front O2 sensors. The green and blue traces are the rear O2 sensor signals.
22. This stacked chart shows the timing signals and the injector waveforms. Note the injectors are out of sequence and the orange trace shows 50ms of on time. This is a logic problem in the PCM.
24. This is the same waveform that has the Honda logic problem spike but the format has been changed. Note the yellow trace spike aligns with the falling edge of the module signal. This occurs when the coil is fired.
26. The yellow, red, green, and blue traces are the signals to the ignition modules in the coil on plug system. The white and purple traces are timing signals sent from the distributor.
28. This GM 3100 was missing. When checking the injector voltage waveform the green trace does not have the closing bump which indicated the injector did not open.
30. This Nissan was missing. When the injector voltage waveforms were checked the current in the yellow trace was low. The green trace shows proper current. The connection was bad at the injector.
1. CAN high speed bus at 2MS
3. CAN high speed bus at 4MS and 8MS
5. CAN high speed bus at 4MSand 8MS dual screen
7. CAN high speed bus at 16MS
9. CAN high speed bus at 100MS
11. Multi Tool, Measure, & Deep Record
13. Setup & Dual Scope
15. Setup & Outputs
1: 3.8 Liter Chevy Injectors and Timing Signals
3: Dodge 2.2 Liter Timing Signals on
5: Ford Crank Sensor and Cam Sensor
7: RX7 Ignition Timing Pulses and Ignition Coils
Eight channels are required to understand
this complex timing system
9: Honda Coil Feedback Causing Flooding
Channel 1 has a negative spike that aligns with Channel 5
coil pulse. This is a good demonstration of the power of having 8 channels.
11. Honda Logic Problem Causing Flooding
13. This vehicle was towed in with a no start. When the fuel pressure was tested there was only 5PSI. The fuel gauge had a reading of ¼ tank. The fuel pump current was the next test. The amp clamp was placed at the fuel pump relay. Note the Freq (Hz) is 152.91 and multiply this by 60 sec. to find the RPM of the fuel pump was 9174.6 RPM. This fuel pump was rotating too fast. Possible causes are no fuel in the tank or the fuel pump had separated from the electric motor.
15. This shows the crank sensor in red, the rectified RPM signal in yellow and the EST signals in blue and green.
19. This signal is from a Windstar van. The yellow trace is the CAM sensor signal. The red trace is the crank sensor signal.
21. This vehicle was cutting out. The yellow trace is the MAF signal, red trace is the 12V power, and green trace is ground.
23. This stacked chart shows the injector signals on top and the timing signals that are sent to the COP module. Note the yellow trace has a downward spike.
25. This is the ignition coil secondary arcing to the primary. This high voltage entering the primary circuit was causing an intermittent stalling problem by putting the PCM into a reset.
27. The purple trace is the timing signal from the distributor. Note the yellow, red, green, and blue traces are the signals that are sent to the ignition modules in the coil on plug system. When signals are laid on top of each other it becomes easier to see which signal affects other signals.
29. This PT Cruiser was towed in. When the injector voltage waveform was checked, three of the four injectors showed low current. The green trace shows the proper current. The connector under the intake had a bad connection.
31. These signals are off of a Jeep computer controlled carburetor.
35. This is a Ford Contour with two time bases being displayed. The yellow trace is the MAF sensor signal. The red trace is the O2 sensor signal. The green trace is the TPS sensor signal. Note on the top chart the humps in the yellow trace are the individual cylinders pulling air past the MAF sensor
17 &18. These signals are during cranking. The yellow and red traces are distributor timing signals. The green trace is the coil primary. The blue trace is the ASD primary or control side of the relay. The white trace is the secondary side of the ASD relay. The purple trace is the signal from the logic module to the power stage for the module.