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Sequoia Toyota Tacoma I рестайлинг

Engine Controls - System & Component Testing - V6 & V8 ~1452 words

Sequoia

  1. Remove glove box and heater duct for access to ECM. For illustration of ECM location, see «THEORY & OPERATION»(ref-133195) article. Note ECM electrical connector terminal identification. (Scheme 437)
  2. Turn ignition on. Using voltmeter, check voltage between terminals No. 16 (Black/Red wire) at ECM electrical connector E4 and No. 17 (Brown wire) at ECM electrical connector E7. This is the +B and E1 terminals at ECM. Voltage should be 9-14 volts. If voltage is within specification, diagnose by symptom. See «TROUBLE SHOOTING - NO CODES»(ref-133220) article. If voltage is not within specification, check for open in wiring harness and electrical connectors between terminal No. 17 (Brown wire) at ECM electrical connector E7 and body ground. See «WIRING DIAGRAMS»(ref-133228) article. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary.
  3. Ensure ignition is off. Check for open and short in Black/Red wire between EFI main relay and terminal No. 16 at ECM electrical connector E4. See «WIRING DIAGRAMS»(ref-133228) article. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring is okay, go to next step. If wiring is defective, repair as necessary.
  4. Turn ignition on. Using voltmeter, check voltage between body ground and terminal No. 9 (Black/Orange wire) at ECM electrical connector E4. This is the IGSW terminal at ECM. Voltage should be 9-14 volts. If voltage is not within specification, go to next step. If voltage is within specification, go to step 8.
  5. Check for defective IGN1 fuse. IGN1 fuse is located in fuse/relay box behind driver's side of instrument panel. If IGN1 fuse is okay, go to next step. If IGN1 fuse is defective, repair short in wiring harness and components connected to IGN1 fuse. See «WIRING DIAGRAMS»(ref-133228) article.
  6. Check ignition switch. See «IGNITION SWITCH»(ref-133222-S01216685292002022500000) under ENGINE SENSORS & SWITCHES. If ignition switch is okay, go to next step. If ignition switch is defective, replace ignition switch. See IGNITION SWITCH under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article.
  7. Check wiring harness and electrical connectors between battery and ignition switch, and between ignition switch and terminal No. 9 (Black/Orange wire) at ECM electrical connector E4. See «WIRING DIAGRAMS»(ref-133228) article. If necessary to check AM2 fuse, AM2 fuse is located in fuse/relay box at driver's side front corner of engine compartment. Repair wiring harness or electrical connectors as necessary.
  8. Ensure ignition is on. Using voltmeter, check voltage between body ground and terminal No. 5 (Black/White wire) at ECM electrical connector E4. This is the MREL terminal at ECM. Voltage should be 9-14 volts. If voltage is within specification, go to next step. If voltage is not within specification, check ECM ground circuit. See «WIRING DIAGRAMS»(ref-133228) article. If ECM ground circuit is defective, repair ground circuit as necessary. If ECM ground circuit is okay, replace ECM. If ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.
  9. Check for defective EFI No. 1 fuse. EFI No. 1 fuse is located in fuse/relay box at driver's side front corner of engine compartment. If EFI No. 1 fuse is okay, go to next step. If EFI fuse is defective, repair short in wiring harness and components connected to EFI fuse. See «WIRING DIAGRAMS»(ref-133228) article.
  10. Check operation of EFI main relay. See «EFI MAIN RELAY»(ref-133222-S01693411942002021900000) under MODULES, MOTORS, RELAYS & SOLENOIDS. If EFI main relay operates properly, go to next step. If EFI main relay is defective, replace EFI main relay.
  11. Check for open and short in wiring harness and electrical connectors between terminal No. 5 (Black/White wire) at ECM electrical connector E4 and EFI main relay, and for open in White/Black wire between EFI main relay and body ground. See «WIRING DIAGRAMS»(ref-133228) article. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary.
  12. Check wiring harness and electrical connectors between battery and EFI No. 1 fuse. See «WIRING DIAGRAMS»(ref-133228) article. Repair wiring harness or electrical connectors as necessary.
  1. Remove passenger's side lower instrument panel cover for access to ECM. For illustration of ECM location, see «THEORY & OPERATION»(ref-133195) article. Note ECM electrical connector terminal identification. (Scheme 438)
  2. Turn ignition on. Using voltmeter, check voltage between terminals No. 16 (Black/Red wire) at ECM electrical connector E8 and No. 17 (Brown wire) at ECM electrical connector E11. This is the +B and E1 terminals at ECM. Voltage should be 9-14 volts. If voltage is within specification, diagnose by symptom. See «TROUBLE SHOOTING - NO CODES»(ref-133220) article. If voltage is not within specification, check for open in wiring harness and electrical connectors between terminal No. 17 (Brown wire) at ECM electrical connector E11 and body ground. See «WIRING DIAGRAMS»(ref-133228) article. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary.
  3. Ensure ignition is off. Check for open and short in Black/Red wire between EFI main relay and terminal No. 16 at ECM electrical connector E8. See «WIRING DIAGRAMS»(ref-133228) article. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment. If wiring is okay, go to next step. If wiring is defective, repair as necessary.
  4. Turn ignition on. Using voltmeter, check voltage between body ground and terminal No. 2 (Black/Orange wire) at ECM electrical connector E8. This is the IGSW terminal at ECM. Voltage should be 9-14 volts. If voltage is not within specification, go to next step. If voltage is within specification, go to step 8.
  5. Check for defective IGN fuse. IGN fuse is located in fuse box behind driver's side of instrument panel. If IGN fuse is okay, go to next step. If IGN fuse is defective, repair short in wiring harness and components connected to IGN fuse. See «WIRING DIAGRAMS»(ref-133228) article.
  6. Check ignition switch. See «IGNITION SWITCH»(ref-133222-S01216685292002022500000) under ENGINE SENSORS & SWITCHES. If ignition switch is okay, go to next step. If ignition switch is defective, replace ignition switch. See IGNITION SWITCH under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article.
  7. Check wiring harness and electrical connectors between battery and ignition switch, and between ignition switch and terminal No. 2 (Black/Orange wire) at ECM electrical connector E8. See «WIRING DIAGRAMS»(ref-133228) article. If necessary to check AM2 fuse, AM2 fuse is located in fuse/relay box at driver's side front corner of engine compartment. Repair wiring harness or electrical connectors as necessary.
  8. Ensure ignition is on. Using voltmeter, check voltage between body ground and terminal No. 8 (Yellow/Green wire) at ECM electrical connector E8. This is the MREL terminal at ECM. Voltage should be 9-14 volts. If voltage is within specification, go to next step. If voltage is not within specification, check ECM ground circuit. See «WIRING DIAGRAMS»(ref-133228) 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.
  9. Check for defective EFI fuse. EFI fuse is located in fuse/relay box at driver's side front corner of engine compartment. If EFI fuse is okay, go to next step. If EFI fuse is defective, repair short in wiring harness and components connected to EFI fuse. See «WIRING DIAGRAMS»(ref-133228) article.
  10. Check operation of EFI main relay. See «EFI MAIN RELAY»(ref-133222-S01693411942002021900000) under MODULES, MOTORS, RELAYS & SOLENOIDS. If EFI main relay operates properly, go to next step. If EFI main relay is defective, replace EFI main relay.
  11. Check for open and short in wiring harness and electrical connectors between terminal No. 8 (Yellow/Green wire) at ECM electrical connector E8 and EFI main relay, and for open in White/Black wire between EFI main relay and body ground. See «WIRING DIAGRAMS»(ref-133228) article. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary.
  12. Check wiring harness and electrical connectors between battery and EFI fuse. See «WIRING DIAGRAMS»(ref-133228) article. Repair wiring harness or electrical connectors as necessary.