How to Use the AUTOOL LM160 Smart Digital Manifold
Use the AUTOOL LM160 by defining the exact A/C test first, closing both control valves, inspecting every hose and fitting, connecting both temperature probes before startup, installing four AA batteries, selecting the verified refrigerant and units, and zeroing both disconnected pressure channels at atmosphere. Map T1 and T2 to the required pipes, establish one stable operating condition, then record LP, HP, EV, CO, T1, T2, SH and SC together.
The LM160 combines dual-pressure measurement, two pipe-temperature channels, 95 refrigerant datasets, Refrigeration, Pressure Leak Test and Evacuation modes, and an eight-language interface. Those functions organize evidence; they do not identify an unknown refrigerant, choose a vehicle charge mass, prove a deep vacuum or locate a leak by themselves.
Updated August 27, 2026.
In this guide
What the LM160 can show
The AUTOOL LM160 reads low- and high-side gauge pressure at the same time. With the correct refrigerant selected, it converts those pressures into evaporation (EV) and condensation (CO) saturation temperatures. With T1 and T2 attached to the correct pipes, Refrigeration mode also displays pipe temperatures and calculated superheat (SH) and subcooling (SC).
Its normal pressure measurement range is 0–60 bar, while the exact manual separately identifies a 65 bar overload value and a 100 bar device pressure limit. None is permission to approach those limits. The lowest working rating among the vehicle, manifold, hose, coupler and adapter controls the job.
Before you connect
Open the AUTOOL manual download center and match the LM160 manual to the controls in your hand. Obtain the verified refrigerant, service-port layout, specified charge mass, oil requirement, operating test condition, recovery method, evacuation target and pressure-test rule from exact vehicle or equipment service information.
Inventory the delivered kit: LM160, red/blue/yellow hoses, two wired clamps, adapters or couplers, case and four matched 1.5 V AA batteries. Confirm connector compatibility and working pressure from the component markings rather than color alone.
Wear eye and hand protection, work with ventilation and use compliant recovery and low-loss service equipment. Keep hoses and probe leads away from fans, belts, exhaust heat and energized terminals.
Stop: Do not connect an unknown or contaminated system, pressure-test with oxygen or unregulated shop air, vent refrigerant to clear a hose, exceed the lowest component rating or open a control valve before tracing the entire flow path.

Understand the controls and ports
The blue knob controls the low-pressure path and the red knob controls the high-pressure path. Turning left opens a valve; turning right closes it. The lower connections are the low side, center filling or evacuation path, and high side. The screen menu offers Pressure Leak Test, Refrigeration and Evacuation. Arrow, Return, Setting/Sound, Unit, OK, P=0 and Power/Backlight keys control selection and measurement setup.
LM160 step-by-step operating procedure
Step 1: Define the exact job
Choose one purpose: stabilized running diagnosis, procedure-controlled evacuation observation or an approved isolated pressure-change test. Write down the refrigerant, connection map, required system state, target fields, stabilization time and shutdown method.
Completion check: Every connection, condition and acceptance value comes from exact service information.
Step 2: Inspect the LM160 and pressure path
Close both control knobs by hand. Inspect the screen, hook, handrails, sight window, probe sockets, brass threads, hoses, couplers, gaskets and valve stems. Replace any damaged, hardened, contaminated or incorrectly rated part. If the manifold or a hose has suffered an impact, remove it from service for evaluation.
Completion check: The complete path is clean, closed, compatible and rated for the expected state.

Step 3: Inventory the kit and connect both probes
Inspect both clamp connectors, leads, jaw springs and contact surfaces. Connect T1 and T2 before powering on; otherwise the instrument may not display their temperatures. Label the channels and write down the pipe each one will measure.
Completion check: Both probes are seated and their eventual pipe locations are unambiguous.
Step 4: Install four AA batteries and configure the interface
Open the rear battery compartment and install four matched 1.5 V AA batteries with correct polarity. Power on, check the battery icon and display segments, then set the language, backlight duration and auto-off period for the job.
Completion check: The display is stable and the power settings can support the complete measurement.
Step 5: Select the refrigerant and units
Enter Refrigeration mode, use the arrows to select the verified refrigerant from the 95-dataset list and press OK. Select pressure and temperature units that match the job sheet. Set vacuum units before starting Evacuation because units cannot be changed while a measurement is running.
Completion check: Refrigerant, pressure, temperature and vacuum units match the written procedure.
Step 6: Zero both channels at atmosphere
Keep both valves closed and leave every pressure inlet open to clean atmosphere. Hold P=0 until the zero message completes and disappears. Repeat atmospheric zeroing before each measurement; never zero while a hose contains pressure or vacuum.
Completion check: Both disconnected pressure channels show zero.

Step 7: Attach and map T1 and T2
Clamp each sensor to clean metal at the pipe location required by service information, not over insulation, paint or a fitting. Ensure full jaw contact, route both leads safely and allow readings to stabilize. Do not infer suction or liquid-line identity from clamp color.
Completion check: Each stable temperature belongs to one named pipe location.
Step 8: Hang the manifold and trace all three hoses
Use the foldable hook so the LM160 remains upright and visible. Trace blue to the verified low-side port, red to the high side and yellow to the required recovery, vacuum or charging equipment. Follow the vehicle and low-loss coupler instructions for connection order while both manifold valves remain closed.
Stop: If a fitting resists, a connection leaks, a hose identity is uncertain or a line can contact moving or hot parts, isolate and correct the setup.
Completion check: Every connection is traced end to end and neither valve opened unintentionally.
Step 9: Establish one repeatable operating condition
For running diagnosis, set engine speed, blower and load, doors, airflow, fan command and ambient measurement exactly as required. Observe from a safe position and wait for compressor operation, pressures and temperatures to stabilize.
Completion check: The complete operating state is recorded before any result.

Step 10: Capture the complete Refrigeration screen
Record LP, HP, EV, CO, T1, T2, SH and SC at the same moment. Verify that the selected refrigerant, service ports and probe locations support each displayed field. A plausible SH or SC value can still be wrong when a clamp is loose, swapped or placed on the wrong pipe.
Completion check: All eight fields represent one stable condition and are compared with the exact vehicle window.
Step 11: Diagnose before moving refrigerant
Check airflow, fan operation, compressor command, clutch or variable-displacement control, sensor data, restrictions and test stability in the specified sequence. Do not add or remove refrigerant merely to make one pressure look familiar. If charge service is justified, recover and charge by the prescribed process and mass.
Completion check: Setup and control faults are separated from a refrigerant-quantity decision.

Step 12: Use Evacuation mode within its measurement limit
Recover refrigerant first. Zero at atmosphere, connect the center path to compliant evacuation equipment and enter Evacuation. Start the test and record duration, current pressure, ambient temperature, water evaporation temperature and Delta T as trend data.
Although the interface offers a Micron unit, the LM160 specification identifies a relative vacuum range of about -1 to 0 bar. Use a clean dedicated absolute vacuum gauge at the required system location for a micron target and decay acceptance.
Completion check: Evacuation acceptance comes from the specified absolute target, stabilization and hold—not a relative trend alone.

Step 13: Run Pressure Leak Test inside a defined procedure
Use only the approved medium and a regulated source. After atmospheric zeroing and system stabilization, enter Pressure Leak Test, establish the required test pressure and press OK to start. Record start pressure, current pressure, pressure difference, elapsed time and temperature. Stop and clear the test before repeating it under a corrected condition.
Completion check: Medium, pressure, temperature, duration and pass/fail criterion are documented together.
Step 14: Isolate, disconnect and store
Stop the measurement, close both knobs and return the vehicle and service equipment to the required shutdown state. Manage trapped refrigerant through compliant recovery or low-loss equipment, disconnect in the prescribed order and restore the service-port caps. Clean probe contacts and fittings, protect all ports and remove batteries before extended storage.
Completion check: No refrigerant was intentionally vented, all ports are restored and the complete result is saved.
Reliable LM160 data gates
| Gate | Pass condition | Stop or repeat when |
|---|---|---|
| Identity | Exact refrigerant and units are verified | Selection is guessed from pressure |
| Zero | Both inputs are open to atmosphere | A hose held pressure during P=0 |
| Probes | T1/T2 contact named pipes fully | A clamp is loose, insulated or swapped |
| Condition | Load, airflow and compressor state are stable | Values come from a changing condition |
| Decision | LP, HP, EV, CO, T1, T2, SH and SC agree with vehicle data | One number drives a charge decision |
Common LM160 problems
A pressure channel will not zero
Disconnect every pressure and vacuum source, manage trapped pressure through approved equipment and let the sensor stabilize. Persistent offset requires evaluation rather than mental correction.
T1 or T2 is blank or unstable
Power down, reseat the probe connector, inspect the lead and ensure the jaws contact clean metal fully. Preserve pipe identity if you swap channels as a controlled check.
SH or SC looks implausible
Recheck the refrigerant selection, probe mapping, pipe location, jaw contact, airflow and operating stability before changing refrigerant quantity.
Pressure changes during the timed test
Record temperature and check external hoses, couplers, valves and adapters. A pressure trend does not locate a leak or prove that the vehicle circuit is responsible.
AUTOOL LM160 FAQ
How many refrigerants does LM160 support?
The exact LM160 manual lists 95 refrigerant pressure-temperature datasets.
Does LM160 use two temperature clamps?
Yes. Connect both probes before startup and map T1 and T2 to the required pipes.
Can the Micron display replace an absolute vacuum gauge?
No. Use the dedicated absolute gauge and decay criterion specified by the procedure.
What batteries does LM160 use?
Four 1.5 V AA batteries.
The reliable LM160 workflow
Define the test, inspect and close both pressure paths, connect the two probes before startup, install four AA batteries, select the exact refrigerant and units, zero both open-air channels, map T1 and T2, trace every hose, stabilize the system and capture LP, HP, EV, CO, T1, T2, SH and SC together. Keep Evacuation and Pressure Leak Test within their evidence limits, then isolate and disconnect without venting.








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