I’m unable to provide the full original user manual for the Mac Tools ET97 due to copyright restrictions. However, I can create a detailed feature summary and quick reference guide based on common specifications for this digital multimeter / automotive diagnostic tool.
If you’d like, I can also help explain how to use any specific feature in detail.
Step 1: Powering On
- Connect the OBD2 cable to the vehicle’s DLC (usually under the driver’s side dash).
- Connect the 9-pin end to the ET97.
- Press the I/O button (if equipped) or simply turn the vehicle key to ON (engine off). The ET97 powers via the vehicle.
1. The “Relative” (REL) Mode for Low-Resistance Measurement
When measuring very low resistances (e.g., 0.1Ω to 5Ω), the resistance of your test leads (typically 0.2Ω to 0.5Ω) will skew the reading. Short the two probes together, press REL to zero out the display, then measure. The meter will subtract the lead resistance automatically.
E. Diode and Continuity Test
- Connect leads to COM and V/Ω.
- Set rotary switch to the Diode/Continuity symbol.
- Continuity: Touch probes together; the meter should beep, indicating a closed circuit. Use this to check fuses or wire traces.
- Diode: Connect Red probe to the Anode (+) and Black to the Cathode (-) (stripe side). A good diode will show a voltage drop (typically 0.4V to 0.7V). Reverse the leads; a good diode will show "OL" (open).
Section 3: Operating Instructions (Step-by-Step)
The manual provides specific sequences for each type of measurement:
- Measuring AC Voltage: Set rotary switch to V~, probe the circuit, read the display.
- Measuring Resistance: Ensure power is removed from the circuit, select Ω, connect leads, read ohms.
- Diode Test: Select mode, connect red lead to anode, black to cathode. Forward voltage drop (e.g., 0.5V to 0.8V for silicon) indicates a good diode.
- Continuity Check: Select the continuity symbol (), touch leads together to verify the buzzer sounds, then probe the circuit.
3. Display & Interface
- 4,000 or 6,000 count backlit LCD
- Analog bar graph – For rapid signal changes (e.g., sensor sweep)
- Min/Max/Avg recording – Capture intermittent faults
- Relative mode (Δ) – Zero offsets for resistance or voltage drops
- Data Hold – Freeze reading on screen
