Oscilloscope Patterns and Waveforms

1993 Dodge Colt L4-1468cc 1.5L SOHCSECTION Oscilloscope Patterns and Waveforms




WAVE PATTERN INSPECTION USING AN ANALYZER MEASUREMENT METHOD
1. Disconnect the camshaft position sensor & crankshaft position sensor connector and connect the special tool (test harness: MB991348) in between. (All terminals should be connected.)

2. Connect the analyzer special patterns pickup to camshaft position sensor & crankshaft position sensor connector terminal A. (When checking the camshaft position sensor signal wave pattern)

3. Connect the analyzer special patterns pickup to camshaft position sensor & crankshaft position sensor connector terminal 3%. (When inspecting the crankshaft position sensor signal wave pattern.)


ALTERNATE METHOD (TEST HARNESS NOT AVAILABLE)
1. Connect the analyzer special patterns pickup to ECM terminal 68. (When inspecting the camshaft position sensor signal wave pattern.)

2. Connect the analyzer special patterns pickup to ECM terminal 69. (When inspecting the crankshaft position sensor signal wave pattern.)





STANDARD WAVE PATTERN
Wave pattern observation points: Check to be sure that cycle time T becomes shorter when the engine speed increases.

EXAMPLES OF ABNORMAL WAVE PATTERNS






Example 1

Cause of problem - Sensor interface malfunction

Wave pattern characteristics - Rectangular wave pattern is output even when the engine is not started.






Example 2

Cause of problem - Loose timing belt, Abnormality in sensor disk

Wave pattern characteristics - Wave pattern jumps to the left or right.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.