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ECU - Precautions


91audi01

Group: 28

Number: 91-03

Date: March 31, 1991


Subject: Electronic Control Units - Subsequential Damage


Model(s): All Models


Care must be taken when working on all vehicles equipped with electronic control units of any types. The following precautions should be followed to assure that you do not inadvertently cause damage to these units during related repairs.

^ Always wait a minimum of 30 seconds after switching off ignition, before connecting or disconnecting a control unit from the vehicle electrical system.

^ Never disconnect a control unit from the electrical system, with the vehicle running.