Using Your Oscilloscope (SUSTIPS 1212-04)

1998 Subaru Forester L, StandardSECTION Using Your Oscilloscope (SUSTIPS 1212-04)
WARNING: This page is about the Forester Base, which is a different variant/trim than selected.
Publication date: 2012-12-01
Reference number: SUSTIPS 1212-04

USING YOUR OSCILLOSCOPE

USING YOUR OSCILLOSCOPE

TECHNICAL INFORMATION TECH TIPS

Reference Number(s): SUSTIPS 1212-04, Date of Issue:  December 01, 2012
SUBARU: All Models

SERVICE INFORMATION

All probing of wires should always be done at the ECM, Always make sure your vehicle's battery is fully charged.

The following information comes from Service Bulletin 11-125-12 which recommends using the oscilloscope to check all 4 camshaft position sensors.

  • Gain access to the vehicle ECM and identify the signal wires using the input/output chart applicable to the vehicle you are working on.
  • Back probe the wires using a suitable pin at the ECM connector.
  • Connect the SDI box to the DLC (Data Link Connector).
  • Connect the gray analog oscilloscope box to the left side connector on tie SDI box.
  • Connect the SDI box to the Toughbook with the USB cable.
  • Turn the ignition switch to the "on" position, engine off.
  • Activate the Subaru Select Monitor software.
  • At the main menu page, click on the oscilloscope function.
  • Press the F2 key to hold the data (Start and Stop).
  • You can monitor up to 4 signals at any one time, an example would be all 4 camshaft position sensors.
  • Press the F7 key (Range).
  • Set ranges to S volts maximum (again, using the 4 cam sensors as an example) other sensors may have a higher or lower setting.
  • Set minimum range to -1 volt.
  • Set time to 100 milliseconds per division (again, this is based on testing the 4 cam sensors per Service Bulletin 11-125-12 . Other testing will require a different setting of time.)
  • Click on the blue "0" button to lock in all range and time settings.
  • Click the F5 key, input range, and adjust all 4 channels to 5 wits. This will allow you to view a clean and smooth pattern.
  • On the same screen, scroll over to sampling mode and make sure "continuous" is selected. It not, and single is selected, you will only see one piece of information, not a continuous pattern.
  • Connect the common port (black lead wire) to a good body ground.
  • Connect analog channels 1,2,3,4 to the 4 signal wires at the ECM harness connector for the camshaft position sensors.
  • Start the vehicle and immediately press the F2. key to begin viewing your pattern.
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.