PCM Input Signals
- Timing control and triggering of fuel injectors are based on input signals from TDC/CRANK/CYL sensors. These sensors are Permanent Magnet (PM) generator pick-up coils.
- Using a DVOM (preferably with bar-graph function) on low-volt scale, check each sensor for pulse voltage signal at indicated PCM harness terminals with engine cranking. See PCM INPUT SIGNAL & RESISTANCE TEST TERMINALS table. If pulse signal is present, sensor is okay. If pulse signal is not present, go to step 3.
- Turn ignition off. Disconnect PCM connector. Check wiring harness and connectors. Check resistance of each sensor at indicated PCM harness terminals. See PCM INPUT SIGNAL & RESISTANCE TEST TERMINALS table. If resistance is within specification, go to step 4. If resistance is not within specification, go to step 5.PCM INPUT SIGNAL & RESISTANCE TEST TERMINALS
Application PCM Terminals (1) Ohms Integra CRANK B15 & B16 350-700 Ohms CYL B11 & B12 350-700 Ohms TDC B13 & B14 350-700 Ohms Legend CRANK No. 1 B15 & B16 650-900 Ohms CRANK No. 2 B14 & B13 650-900 Ohms CYL No. 1 B12 & B11 650-900 Ohms CYL No. 2 B9 & B10 650-900 Ohms Vigor CRANK B15 & B16 650-850 Ohms CYL B11 & B12 650-850 Ohms TDC B13 & B14 650-850 Ohms
See Fig 1.(1) - Check continuity to ground on each terminal. If continuity exists, disconnect sensor connector, and recheck appropriate PCM terminal for continuity to ground. If continuity still exists, repair short to ground in harness. If continuity does not exist, replace sensor assembly.
- Disconnect sensor connector. Check resistance of sensor. See Fig 2, Fig 3 or Fig 4 . If resistance is within specification, repair open, short or corrosion in sensor harness between PCM and sensor. See PCM INPUT SIGNAL & RESISTANCE TEST TERMINALS table. If sensor resistance is not within specification, replace sensor assembly.