What does electrical shakedown testing include on a commercial truck?

Thread Starter


Joined Jan 4, 2017
A new truck is being built. Some of systems being built in this truck are electrical power steering (EPS) system, Antilock Braking system (ABS), Engine Control Unit (ECU), Transmission Control Unit (TCU), Body Control Module (BCM), Human Machine Interface (HMI), and Instrument cluster.

Is electrical shakedown testing performed on stationary vehicle or while driving a vehicle for certain number of miles?

My understanding is that electrical shakedown testing is minimal testing required to commence comprehensive vehicle and systems tests.

What are comprehensive electrical shakedown tests: I came up with following list so far:

1. Revolution counter reading in instrument cluster.
2. Battery voltage test (Measure battery voltage). Equipment needed voltmeter.
3. Test hazard warning light switch to ensure hazard lights work. The hazard lights must be able to operate without a key in the ignition.
4. Check brake lights turn ON when brake is applied.
5. Checks all the horns work.
6. Test wiper motor to ensure wipers works.
7. Test turn signals switches to ensure turn signals work. The indicators are only powered when the ignition switch is ON.
8. Check that cooling fan draws air from the radiator. Check that fan rotates in correct. Check the fan noise level is acceptable.
9. Test the alternator. Use a suitable ammeter to measure the theoretical maximum output current. Measure the alternator output voltage with engine off, engine running at idle, and engine running at some rpm.
10. Headlights operation.
11. High beam operation.
12. Check if brake pads are getting worn out.
13. Test service brakes.

Thread Starter


Joined Jan 4, 2017
What equipment and tools are needed to perform each electrical test?
What is the test procedure for each electrical shakedown test?
What is the expected result of each electrical shakedown test?


Joined Apr 2, 2020
Is this your company or are you testing for the new truck manufacturer? Is your company supplying the electrical equipment to the truck manufacturer? Is this a school project "what if" scenario?

why is this posted under microcontrollers?

anyhow, a manufacturer typically sets the standard. If they want their own standard, they write their own test procedures and definitions of pass and fail. Otherwise, they often pick an ISO standard, or SAE standard. Usually, tests are done in labs and not on public roads for component level testing. It is just too difficult to find the perfect pothole and expect it to remain in-repaired until the next time the test is run.


Joined Oct 6, 2013
These days most testing can be done simply by connecting to the vehicle's CAN and checking inputs and outputs through a program that systemically goes through everything while the inspector operates switches as needed and monitors outputs. The whole process could be done in a couple minutes. Typically if everything works at the beginning it will still work past the warranty period so in depth testing is kind of pointless to the manufacturer past initial design testing. Since most everything is run off the CAN buss more time needs to be spent making sure it will stay intact and functioning than individual components.

in the case of commercial vehicles engines, transmissions, and such are built to be sold to other end users other than a specific vehicle. Almost always the engine, transmission, ABS, and to some extent axles and braking systems are already in production, or separate products not unique to the end product and will be tested as their own respective system. Engine and transmission controllers and harnesses are already mounted and tested as a complete unit. The truck manufacturer gets the specs of the parts, and builds the truck around them. Obviously there needs to be a bit of final fitment testing to make sure the CAN and power wires hold up, but for the most part there really isn't going to be much testing needed.

Same with the alternator. If a new alternator design is needed the alternator manufacturer will build it to the truck manufacturer's specifications, test it, and certify it works as it was specified to work. Testing beyond that is kind of pointless.

There are testing stands that can shake a whole truck better than thousands of miles down your typical roads for in depth testing. They might run around a short track after leaving the assembly line, but that will be more for vibration and driveablilty issues than in depth testing.

Basically 80% of problems are going to be programming issues rather than physical problems these days.
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