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Home >> Volvo >> 1995 >> 850 Base, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Turbo >> Diagnostic Trouble Code Testing >> MOTRONIC 4.3 Control System >> Code 2-2-3, 2-4-5: Valve Signal Opening, Valve Signal Closing

Code 2-2-3, 2-4-5: Valve Signal Opening, Valve Signal Closing

  1. If fault is permanent and signal is too high, go to next step. If fault is permanent and signal is too low, go to step 4). If fault is intermittent and signal is too high, go to step 8). If fault is intermittent and signal is too low, go to step 9).
  2. Turn ignition off. Disconnect IAC valve. Turn ignition on. Connect voltmeter between ground and IAC valve connector terminal No. 3 (Code 2-2-3) or terminal No. 1 (Code 2-4-5). If voltmeter shows less than one volt, go to next step. On Code 2-2-3, if voltmeter shows more than one volt, check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for a short circuit to voltage. On Code 2-4-5, if voltmeter shows more than one volt, check wiring between IAC valve connector terminal No. 1 and ECM terminal A25 for a short circuit to voltage.
  3. Turn ignition off. Wait about 2 minutes. Disconnect IAC valve. Connect an ohmmeter between IAC valve connector terminals No. 1 and 3. If ohmmeter reads 20-40 k/ohms, test using new IAC valve. If ohmmeter shows about zero ohms, check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for a short circuit to wiring between IAC valve connector terminal No. 1 and ECM terminal A25. If IAC valve signal wiring is shorted to each other, then both Codes 2-2-3 and 2-4-5 will be set.
  4. If fault is permanent and signal is too low, turn ignition off. Disconnect IAC valve. Turn ignition on. Connect voltmeter between IAC valve connector terminal No. 2 and ground. If voltmeter shows battery voltage, go to next step. If voltmeter does not show battery voltage, check wiring between main relay connector terminal No. 3 and IAC valve connector terminal No. 2 for an open circuit. If there is an open circuit in voltage lead, both Codes 2-2-3 and 2-4-5 will be set.
  5. Turn ignition off. Wait about 2 minutes. Disconnect IAC valve connector. Connect an ohmmeter between ground and IAC valve connector terminal No. 3 (Code 2-2-3) or No. 1 (Code 2-4-5). If ohmmeter reads 10-20 k/ohms, go to step 7). If ohmmeter reads infinite resistance, go to next step. If ohmmeter shows about zero ohms, on Code 2-2-3, check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for a short circuit to ground. On Code 2-4-5, check wiring between IAC valve connector terminal No. 1 and ECM terminal A25 for a short to ground.
  6. Turn ignition off. Disconnect IAC valve connector. Ensure ECM connector terminals are clean and tight, and free of oxidation. Reconnect ECM connector. Connect an ohmmeter between ground and IAC valve connector terminal No. 3 (Code 2-2-3) or terminal No. 1 (Code 2-4-5). If ohmmeter reads 10-20 k/ohms, cause of code was poor contact in ECM connector. If ohmmeter does not show 10-20 k/ohms, on Code 2-2-3, check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for an open circuit. On Code 2-4-5, check wiring between IAC valve connector terminal No. 1 and ECM terminal A25 for an open circuit.
  7. Turn ignition off. Disconnect IAC valve. Connect ohmmeter between IAC valve connector terminals No. 1 and 2, then between terminals No. 2 and 3. If ohmmeter reads 9-14 ohms in both cases, cause of code is poor contact in IAC valve connector. Repair as necessary. If ohmmeter does not read 9-14 ohms in both cases, test using new IAC valve.
  8. If fault is intermittent and signal is too high, on Code 2-2-3, check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for an intermittent short to voltage or intermittent short circuit to coil signal voltage. On Code 2-4-5, check wiring between IAC valve connector terminal No. 1 and ECM terminal A25 for an intermittent short to voltage or intermittent short circuit to coil signal voltage.
  9. If fault is intermittent and signal is too low on Code 2-4-5, go to next step. On Code 2-2-3, check IAC valve and ECM connectors for contact resistance and oxidation. Repair as necessary. Check wiring between main relay connector terminal No. 3 and IAC valve connector terminal No. 2 for an intermittent open circuit. Also check wiring between IAC valve connector terminal No. 3 and ECM terminal A11 for an intermittent open circuit or short circuit to ground.
  10. On Code 2-4-5, check IAC valve and ECM connectors for contact resistance and oxidation. Repair as necessary. Check wiring between main relay connector terminal No. 3 and IAC valve connector terminal No. 2 for an intermittent open circuit. Also check wiring between IAC valve connector terminal No. 1 and ECM terminal A25 for an intermittent open circuit or short circuit to ground.
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