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Starter Signal Circuit: MR2

  1. If Toyota hand-held tester is available, go to next step. If Toyota hand-held tester is not available, go to step  5.
  2. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. See Figure. Turn ignition on and then turn hand-held tester on. Read STA signal display on hand-held tester with ignition on, and with ignition switch in START position and engine cranking. STA signal display should read OFF with ignition on, and ON with ignition switch in START position. If STA signal display is not as specified, go to next step. If STA signal display is as specified, diagnose by symptom. See TROUBLE SHOOTING - NO CODES article.
  3. Check for open and short in Black wire between starter relay and starter fuse, defective starter fuse, and for open and short in Black wire and electrical connectors between starter fuse and terminal No. 11 at Engine Control Module (ECM) electrical connector E3. This is the starter signal circuit between starter relay and ECM. See WIRING DIAGRAMS article. Starter relay and starter fuse are located in fuse/relay box at driver's side rear corner of engine compartment, just in front of strut tower and may be marked as ST relay and ST fuse. ECM is located on inside of firewall, directly behind driver's seat and luggage compartment. For illustration of ECM location, see THEORY & OPERATION article. To remove components for access to ECM, see ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article. For ECM electrical connector terminal identification, see Figure.
  4. If starter fuse, wiring harness or electrical connector is defective, replace fuse or repair wiring harness or electrical connector as necessary. If starter fuse, wiring harness and electrical connectors are okay, check ECM ground circuit. See WIRING DIAGRAMS article. If ECM ground circuit is defective, repair ground circuit as necessary. If ECM ground circuit is okay, replace ECM. On models equipped with engine immobilizer system, if ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. Models equipped with engine immobilizer system may be identified by looking at the ignition key. On models equipped with engine immobilizer system, the top of the ignition key is thicker than a standard ignition key, as a transponder chip is incorporated into the top of the ignition key. For programming procedures, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.
  5. Remove necessary components for access to Engine Control Module (ECM). ECM is located on inside of firewall, directly behind driver's seat and luggage compartment. See ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article. Remove bolts and disconnect ECM with electrical connectors from inside of firewall.
  6. Note ECM electrical connector terminals. See Figure. Using voltmeter, check voltage between body ground and terminal No. 11 (Black wire) at ECM electrical connector E3 with ignition switch in START position and engine cranking. This is the STA terminal at ECM. Voltage should be 6 volts or more. If voltage is not within specification, go to next step. If voltage is within specification, diagnose by symptom. See TROUBLE SHOOTING - NO CODES article.
  7. Check for open and short in Black wire between starter relay and starter fuse, defective starter fuse, and for open and short in Black wire and electrical connectors between starter relay and terminal No. 11 at ECM electrical connector E3. This is the starter signal circuit between starter relay and ECM. See WIRING DIAGRAMS article. Starter relay and starter fuse are located in fuse/relay box at driver's side rear corner of engine compartment, just in front of strut tower and may be marked as ST relay and ST fuse.
  8. If starter fuse, wiring harness or electrical connector is defective, replace fuse or repair wiring harness or electrical connector as necessary. If starter fuse, wiring harness and electrical connectors are okay, check ECM ground circuit. See WIRING DIAGRAMS article. If ECM ground circuit is defective, repair ground circuit as necessary. If ECM ground circuit is okay, replace ECM. On models equipped with engine immobilizer system, if ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. Models equipped with engine immobilizer system may be identified by looking at the ignition key. On models equipped with engine immobilizer system, the top of the ignition key is thicker than a standard ignition key, as a transponder chip is incorporated into the top of the ignition key. For programming procedures, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.
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