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Power Mirror Ecu Test

  1. Remove power mirror ECU. See POWER MIRROR ECU  under REMOVAL & INSTALLATION. Disconnect ECU harness connectors. Using an ohmmeter, check for continuity at specified terminals. See POWER MIRROR ECU CONTINUITY TEST  table.
  2. Reconnect ECU harness connectors. Using a voltmeter, check for voltage at specified terminals. See POWER MIRROR ECU VOLTAGE TESTING  table. See Fig 1. If continuity or voltage readings are not as specified, check wiring. If wiring is okay, replace power mirror ECU.
Fig 1: Testing Power Mirror ECU
G92C01029Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
POWER MIRROR ECU CONTINUITY TEST

Application Terminals
Mirror Switch In Rest Position A1 & A2, A1 & A3, A8 & A10, A9 & A10, A11 & Ground, A12 & A13, (1) & A16
Left Mirror Switch Activated
Up B3 & B6
Down B1 & B6
Left B3 & B5
Right B1 & B5
Right Mirror Switch Activated
Up B2 & B3
Down B1 & B2
Left B3 & B4
Right B1 & B4
(1) Terminals No. 1 & 18 of tilt and telescoping ECU. See Fig 2.
Fig 2: Identifying Tilt & Telescoping ECU Harness Connector
G92E01030Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
POWER MIRROR ECU VOLTAGE TESTING

Application (1) Terminals Volts
At All Times A4 Battery
Ignition Switch
In ACC Position A7 Battery
In OFF Position A7 Zero
Left Or Right Mirror Switch (Any Position Except OFF) A13 (2) 5.0
Left Mirror Switch Activated
Up A9 Battery
Down Or Left A10 Battery
Right A8 Battery
Right Mirror Switch Activated
Up A2 Battery
Down Or Right A3 Battery
Left A1 Battery
Left Mirror (3)
Uppermost Position A15 0-0.9
Lowermost Position A15 2.8-5.0
Leftmost Position A14 2.8-5.0
Rightmost Position A14 0-0.9
Right Mirror (3)
Uppermost Position A6 0-0.9
Lowermost Position A6 2.8-5.0
Leftmost Position A5 0-0.9
Rightmost Position A5 2.8-5.0
Mirror Switch At Rest Position B2, B4, B5 & B6 (2) 5.0
(1) All measurements between terminal and ground.
(2) Approximate voltage.
(3) Ensure voltage reading changes as mirror moves.