Acceleration Simulation Mode (ASM) Emission Inspection

Vehicle model-years 1976 - 1999 that are registered in the Enhanced Program area require an ASM inspection; excluding motorhomes and heavy-duty vehicles meeting certain conditions.

The examples below explains:

The ASM emission inspection includes two loaded mode sequences known as the 50/15 test 50% load at 15 MPH and the 25/25 test 25% load at 25 MPH.

Inspectors must ensure that all the applicable before-test-conditions specified in section 1.2.0 are met before beginning the ASM inspection. Once the applicable before-test-conditions are met, follow the EIS prompts to conduct the ASM inspection.

CAUTION! Be aware that some vehicle designs are incompatible with a two wheel drive (2WD) dynamometer. Any attempt to operate such vehicles on a 2WD dynamometer could cause injury and/or may damage the vehicle.

The vehicle can come off the Dyno and several damage will or can occur to you are the vehicle. 

If the vehicle is not compatible with the ASM inspection then a TSI inspection shall be performed.



The following are examples of vehicle designs that are not compatible "can not go on the dyno" with the ASM test and therefore must receive the two-speed-idle test:

• Full-time all wheel or four wheel drive;

• Traction control that cannot be disabled;

• Body or chassis modifications made for business purposes that make the vehicle incompatible with loaded mode testing;

• Unable to safely fit on the dynamometer;

• Motorhomes as classified by the Department of Motor Vehicles over 8,500 GVWR; • Heavy duty vehicles with GVWR between 8,501 and 9,999 and with an unloaded drive axle weight over 5,000 pounds.

• Heavy duty vehicles with GVWR over 9,999.




For the purposes of a Smog Check inspection, the term “unloaded” shall mean that the vehicle is not currently transporting loads for delivery or is not carrying items of a temporary nature (bricks, wood, sand, lumber, etc.).

The GVWR includes items that have been welded, bolted or otherwise permanently affixed to the vehicle, and tools, supplies, parts, hardware, equipment or devices of a similar nature that are routinely carried in or on the vehicle in the performance of the work for which the vehicle is primarily used.

To ensure the appropriate test and emission standards are applied, always follow the EIS prompts. 

This will protect you and the vehicle from damage, always follow the on screen prompts. 

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