How To Reset Car Ecu Without Disconnecting Battery. Easy Way to Reset ECU without battery disconnect With the key in your pocketcar push the Engine Start button TWICE so the car is fully on but not started Within three seconds of the car ON again NOT started Floor all the way down and Release the gas pedal fully 5 times within 5 seconds. 3 Wait 7 seconds then floor the gas pedal and hold for 10 seconds.
Disconnecting the battery for a short time may not do the trick because the cars computer or ECU still has some current in it. Select the fuse that is labeled ECM and remove this fuse. Another possibility is a bad Battery Temperature Sensor.
Now stop open your cars bonnet and remove the lead of earth from the battery.
With accelerator pedal fully released turn ignition switch ON and wait 3 seconds2. Disconnect the negative battery cable using a 18 cm 34 inch spanner to loosen the battery cable. How long should battery be disconnected to reset ECU. Another possibility is a bad Battery Temperature Sensor.
