Do not start the engine with a loose battery.
When the battery is discharged, do not start the engine with a quick battery charger.
Never disconnect the battery while the engine is running.
When charging the battery with a quick charger, disconnect the battery from the electrical system.
Before checking the injection system, make sure that the ignition system is working properly, that is, the ignition and spark plugs correspond to the specified parameters.
At temperatures above +80°С (drying after painting) remove the electronic control unit.
Make sure all connectors are securely connected.
Do not disconnect or connect the ECM connector with the ignition on.
Turn off power to the fuel pump relay when checking compression. On vehicles with DME, pull out the main injection relay (relay -26-).