LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 1997 >> Probe Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 10 (Module Communications Network) >> Testing >> Test C: No Response/Acknowledgment Received From All Modules On Circuit 70
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test C: No Response/Acknowledgment Received From All Modules On Circuit 70

WARNING: This page is about a different car, the 1997 Lincoln Mark VIII. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 5 (Black/Light Blue wire) and No. 7 (Light Blue/White wire) on DLC. See Figure . If voltage does not exist, go to step 9). If voltage exists, go to next step.
  2. Using voltmeter, check voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) on DLC. See Figure . If voltage does not exist, go to step 16). If voltage exists, g o to next step.
  3. Turn ignition switch to OFF position. Disconnect Black 16-pin harness connector C200. Harness connector C200 is located below passenger's side of instrument panel, near kick panel. See Fig 1 .
  4. Using ohmmeter, check resistance between terminal No. 7 (Light Blue/White wire) on DLC and terminal No. 8 (Light Blue/White wire) on female side of harness connector C200. See Fig 2 . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open circuit on Light Blue/White wire on circuit 70 between DLC and harness connector C200. Repeat TEST A  .
    Fig 1: Locating Harness Connector C200
    G97F28485Courtesy of FORD MOTOR CO.
    Fig 2: Checking Resistance Between DLC & Harness Connector C200
    G97G28486Courtesy of FORD MOTOR CO.
  5. Disconnect 16-pin harness connector C304. Harness connector C304 is located below passenger's side front seat and is a square-type connector. See Fig 3 .
  6. Using ohmmeter, check resistance between terminal No. 8 (Light Blue/White wire) on male side of harness connector C200 and terminal No. 1 (Light Blue/White wire) on female side of harness connector C304. See Fig 3 . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open circuit on Light Blue/White wire between harness connectors C200 and C304 on circuit 70. Repeat TEST A  .
    Fig 3: Identifying Harness Connector C304 & Checking Resistance Between Harness Connectors C200 & C304
    G97H28487Courtesy of FORD MOTOR CO.
  7. Disconnect Gray 22-pin connector C320 from Passenger's Seat Module (PSM). The PSM is located below passenger's side front seat.
  8. Using ohmmeter, check resistance between terminal No. 1 (Light Blue/White wire) on male side of harness connector C304 and terminal No. 22 (Light Blue/White wire) on connector C320 for PSM. See Fig 4 . If resistance is 5 ohms or less, go to step 15). If resistance is more than 5 ohms, go to next step.
    Fig 4: Checking Resistance Between Harness Connector C304 & Connector C320
    G97I28488Courtesy of FORD MOTOR CO.
  9. Turn ignition switch to OFF position. Disconnect Black 16-pin harness connector C200 if not previously disconnected. Harness connector C200 is located below passenger's side of instrument panel, near kick panel. See Fig 1 .
  10. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 5 (Black/Light Blue wire) and No. 7 (Light Blue/White wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White between DLC and harness connector C200. Repeat TEST A  .
  11. Turn ignition switch to OFF position. Reinstall harness connector C200. Disconnect 16-pin harness connector C304 if not previously disconnected. Harness connector C304 is located below passenger's side front seat and is a square-type connector. See Fig 3 .
  12. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 5 (Black/Light Blue wire) and No. 7 (Light Blue/White wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White in wiring harness part No. 14A005. See Figure . Repeat TEST A  .
  13. Turn ignition switch to OFF position. Reinstall harness connector C304. Disconnect Gray 22-pin connector C320 from Passenger's Seat Module (PSM). The PSM is located below passenger's side front seat.
  14. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 5 (Black/Light Blue wire) and No. 7 (Light Blue/White wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White between PSM and harness connector C304. Repeat TEST A  .
  15. Inspect terminal No. 22 on Gray 22-pin connector C320 for PSM for damage. Also inspect corresponding pin on PSM for damage. If terminal on connector C320 and pin on PSM are okay, replace PSM. Repeat TEST A  . If terminal on connector C320 or pin on PSM are damaged, repair as needed. Repeat TEST A  .
  16. Turn ignition switch to OFF position. Disconnect Black 16-pin harness connector C200. Harness connector C200 is located below passenger's side of instrument panel, near kick panel. See Fig 1 .
  17. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White between DLC and harness connector C200. Repeat TEST A  .
  18. Turn ignition switch to OFF position. Reinstall harness connector C200. Disconnect 16-pin harness connector C304. Harness connector C304 is located below passenger's side front seat and is a square-type connector. See Fig 3 .
  19. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White in wiring harness part No. 14A005. See Figure . Repeat TEST A  .
  20. Turn ignition switch to OFF position. Reinstall harness connector C304. Disconnect Gray 22-pin connector C320 from Passenger's Seat Module (PSM). The PSM is located below passenger's side front seat.
  21. Turn ignition switch to ON position. Using voltmeter, check voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) on DLC. See Figure . If voltage exists, go to next step. If voltage does not exist, repair Light Blue/White between PSM and harness connector C304. Repeat TEST A  .
  22. Inspect terminal No. 22 on Gray 22-pin connector C320 for PSM for damage. Also inspect corresponding pin on PSM for damage. If terminal on connector C320 and pin on PSM are okay, replace PSM. Repeat TEST A  . If terminal on connector C320 or pin on PSM are damaged, repair as needed. Repeat TEST A  .
scientia non olet · About LEMON Manuals