Run a Timed Pressure-Hold Check, Then Trace the Leak With Smoke
The SML400 runs an automatic 180-second pressure-hold routine and shows a PASS or ERR result, then switches to Smoke mode so you can see where air escapes. Its built-in pump runs from 12 V, so no shop air is needed; set pressure from the vehicle procedure, not the machine’s maximum.
- 180 s Pressure Hold
- PASS / ERR Result
- Built-In Pump
- Air, Hold & Smoke Modes
- Expanded Adapter Kit
Key Features
-
Three Test Modes
Run Air mode or the three-minute pressure-hold routine first, then use Smoke mode to inspect an indicated escape path.
-
Countdown and Result on Screen
The display shows the hold countdown and the routine’s PASS or ERR result for the configured sealed test.
-
Separate Pressure and Flow Readings
Read pressure on the gauge and delivery on the flow meter while filling and checking the test volume.
-
Adjustable Built-In Air
The internal pump supplies test air from the 12 V connection; adjust pressure and flow gradually to the permitted values.
-
Oil Level Gauge and Drain Valve
Check the oil level before use and drain aged or excess fluid before refilling or storage.
-
Overheat Protection
Operation stops when the unit reaches its protection temperature; let it cool before continuing.
What’s in the Box
- 1รSML400 main unit
- 1รPower cable for vehicle-battery connection
- 1รSmoke output hose
- 2รConical adapters
- 2รUniversal airbag adapters
- 1รValve-core wrench
- 1รEVAP service-port connector
- 1รGraduated oil-filling bottle
- 1รSet of universal hard rubber plugs
- 1รSet of red cap plugs
- 1รUniversal soft rubber plug
- 1รBMW oil-cap adapter set
- 1รUser manual

How to Use
- Confirm the procedureIdentify the target system, permitted pressure, access point, valve state and openings to seal.
- Prepare the machineInspect the power lead, hose and adapters, and add or confirm only the smoke oil specified in the manual.
- Connect and isolateSeal the correct adapter to the test point and close normal escape paths per the vehicle procedure.
- Run Air or Pressure modeObserve the gauge or display result under the selected test conditions.
- Trace with smokeSwitch to Smoke mode, let the volume fill, and inspect joints, hoses and seals for escaping smoke.
- Repair and retestRepair the confirmed leak and repeat the same controlled test.
Pressure-hold tests, smoke tracing, oil care and troubleshooting: SML400 user manual (PDF).
Good to Know
Caution
- Do not apply the machine’s maximum output to every system; use the OEM or component procedure and the lowest appropriate setting.
- Use only approved smoke machine fluid; never water, viscous or corrosive liquids.
- Do not operate with damaged power leads, hoses or adapters, and clean an opening before inserting an airbag adapter so sharp edges cannot puncture it.
- Work in a dry, well-ventilated area away from flames and heat, wear eye and hand protection, and keep smoke away from sensitive electronics.
FAQ
Can I use the maximum pressure on an EVAP system?
Do not assume so. Machine capacity and EVAP-safe pressure are different facts; choose pressure from the vehicle procedure.
What if no smoke is visible?
Verify smoke delivery, access, isolation, adapter sealing and valve state, then continue with functional diagnosis; blockage, intermittent or non-leak faults may not produce visible smoke.
Does a visible leak guarantee the entire repair?
It identifies an area to inspect and confirm. Repair the verified problem, repeat the test and complete any required vehicle checks.




































