Home/Plymouth/Neon/Plymouth Neon I (1993-2001)/Repair manual/Testing & Diagnostics/Engine Controls - Tests W/codes - 2.0L: Specifications
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Engine Controls - Tests W/codes - 2.0L: Specifications Plymouth Neon I

Testing & Diagnostics 2 illustrations ~1249 words

TEST TC-12A - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKTS

Note. For connector terminal ID, see CONNECTOR IDENTIFICATION Directory. For wiring diagram, see WIRING DIAGRAMS article.

Scheme 1

Scheme 1: TEST TC-12A - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKTS
  1. If vehicle is not equipped with a manual transaxle, go to next step. If vehicle is equipped with a manual transaxle, this DTC does not apply. Perform TEST VER-2A.
  2. Start engine. Let engine idle for at least 20 seconds. Turn engine off. Turn ignition on. Using scan tool, actuate Torque Converter Clutch (TCC) solenoid. Using scan tool, read Diagnostic Trouble Codes (DTCs). If scan tool displays TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKTS with a run count of zero, go to step 7). If scan tool does not display TORQUE CONVERTER CLUTCH SOLENOID/TRANS CKTS with a run count of zero, go to next step. NOTE: Driving on mountainous terrain can cause this trouble code to set intermittently.
  3. Condition to set trouble code is not present at this time. TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKTS DTC sets when torque converter does not lock and unlock when desired. A minimum amount of improvement of torque converter efficiency is expected after lock-up is achieved. This expected improvement will not be seen if torque converter is malfunctioning. Two consecutive failures over 2 trips will store DTC. Go to next step.
  4. Possible causes are: front tire size is larger than 23.51" (185/65-R14 standard tire size), or smaller than 20.78" (T115/70-D14 spare tire size), low transmission oil level or pressure, debris in transmission oil, incorrect speedometer gear for front wheels, Part Throttle Unlock (PTU) solenoid not securely connected or stuck, malfunctioning lock-up valve in transmission, worn out friction material on friction disc in torque converter, failed gear box, differential, or axle shaft contacts, Powertrain Control Module (PCM) failure or poor wiring connections. Go to next step.
  5. Inspect all related wiring and connectors and repair as necessary. If no problems were found with wiring and connectors, go to next step. If related wiring and connectors were repaired, perform TEST VER-2A.
  6. Using scan tool, read DTCs with actuator test still running. Wiggle wiring harness from the TCC solenoid to PCM. If the TCC solenoid control circuit DTC returned, repair wiring harness as necessary where wiggling caused the problem to appear. Perform TEST VER-2A. If TCC solenoid control circuit DTC did not return, see «INACTIVE TROUBLE CODE CONDITION»(ref-24778-S23565439262001010500000). Test is complete. Perform TEST VER-2A.
  7. Turn ignition off. Disconnect TCC solenoid connector. (Scheme 1) Turn ignition on. Using scan tool in voltmeter mode, check voltage on TCC solenoid connector Light Green/Black wire. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open Light Green/Black wire. Perform TEST VER-2A.
  8. Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Using an external ohmmeter, check resistance of Orange/Black wire between TCC solenoid connector and PCM connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open Orange/Black wire. Perform TEST VER-2A.
  9. Using scan tool in ohmmeter mode, check resistance of PCM connector terminal No. 79 (Orange/Black wire). If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Orange/Black wire. Perform TEST VER-2A.
  10. Reconnect TCC solenoid connector. Turn ignition on. Using scan tool in voltmeter mode, check voltage of PCM connector terminal No. 79 (Orange/Black wire). If voltage is more than 10 volts, replace PCM. Perform TEST VER-2A. If voltage is 10 volts or less, replace TCC solenoid. Perform TEST VER-2A.

TEST TC-148A - TORQUE CONVERTER CLUTCH, NO RPM DROP LOCKUP

Note. For connector terminal ID, see CONNECTOR IDENTIFICATION Directory. For wiring diagram, see WIRING DIAGRAMS article.

Scheme 2

Scheme 2: TEST TC-148A - TORQUE CONVERTER CLUTCH, NO RPM DROP LOCKUP
  1. Start engine and warm to operating temperature. Depress and hold brake pedal. Put transmission in Drive. Using scan tool, actuate Torque Converter Clutch (TCC) solenoid. If engine stalls, go to next step. If engine does not stall, go to step 6).
  2. Restart engine. Depress and hold brake pedal. Put transmission in Drive. Using scan tool, actuate TCC solenoid at zero percent duty cycle. If engine stalls, go to next step. If engine does not stall, go to step 6). NOTE: Driving on mountainous terrain can cause this trouble code to set intermittently.
  3. Condition to set trouble code is not present at this time. TORQUE CONVERTER CLUTCH, NO RPM DROP LOCKUP DTC sets if torque converter malfunctions are detected when torque converter is locked or unlocked. A minimum amount of improvement of torque converter efficiency is expected after lock-up is achieved. This expected improvement will not be seen if torque converter is malfunctioning. Two consecutive failures over 2 trips will store DTC. Go to next step.
  4. Possible causes are: front wheel size is larger than 23.51" (185/65-R14 standard wheel size), or smaller than 20.78" (T115/70-D14 spare tire size), low transmission oil level or pressure, debris in transmission oil, incorrect speedometer gear for front wheels, Part Throttle Unlock (PTU) solenoid not securely connected or stuck, malfunctioning lock-up valve in transmission, worn out friction material on friction disc in torque converter, failed gear box, differential, or axle shaft contacts, Powertrain Control Module (PCM) failure or poor wiring connections. Go to next step.
  5. Inspect all related wiring and connectors and repair as necessary. If no problems were found with wiring and connectors, see «INACTIVE TROUBLE CODE CONDITION»(ref-24778-S23565439262001010500000). Perform TEST VER-2A. If related wiring and connectors were repaired, perform TEST VER-2A.
  6. Check transmission fluid for debris and proper level. If transmission fluid is okay, go to next step. If transmission fluid is not okay, repair as necessary. Perform TEST VER-2A.
  7. Turn ignition off. Disconnect TCC solenoid connector. Turn ignition on. Using scan tool in voltmeter mode, check voltage of TCC solenoid connector Light Green/Black wire. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open Light Green/Black wire. Perform TEST VER-2A.
  8. Using an external ohmmeter, check resistance between TCC solenoid terminals. If resistance is 30-50 ohms, go to next step. If resistance is not 30-50 ohms, replace TCC solenoid. Perform TEST VER-2A.
  9. Reconnect TCC solenoid connector. Disconnect 3-pin Vehicle Speed Sensor (VSS) connector. Remove VSS from transmission. (Scheme 2) Inspect VSS for damage. Replace VSS as necessary. Perform TEST VER-2A. If VSS is okay, go to next step.
  10. Verify front tire size is NOT larger than 23.51" (185/65-R14 standard tire size), or smaller than 20.78" (T115/70-D14 spare tire size). Replace front tires as necessary. Perform TEST VER-2A. If front tires are correct size, go to next step.
  11. Tee a 0-300 psi gauge to transmission cooler in port on transmission. (Scheme 2) Ensure gauge hose is long enough so gauge can be monitored. Road test vehicle. During road test, achieve 50 MPH. Pressure gauge will read approximately 15 psi until lock-up is achieved. If TCC solenoid is operating properly, gauge will jump 10-15 psi higher after lock-up. If gauge jumped 10-15 psi higher, go to next step. If gauge did not jump 10-15 psi higher, replace stuck TCC solenoid or repair torque converter as necessary. Perform TEST VER-2A.
  12. Maintain 50 MPH according to scan tool display. Wait 10 seconds in lock-up, then record engine RPM. If engine speed is 2150-2250 RPM, TCC functioning properly at this time. Perform TEST VER-2A. If engine speed is not 2150-2250 RPM, problem appears to be in differential, output shaft or gear box. Repair transmission as necessary. Perform TEST VER-2A.