850 turbo uses a Motronic 4.3 control system, which has a single Electronic Control Module (ECM) to control fuel injection and ignition systems. In addition, Motronic 4.3 control system incorporates an on-board diagnostic function. Signals from various sensors are monitored continuously. If certain signals are lost or become faulty, ECM will adopt fixed substitute values (limp-home mode) to enable vehicle to be driven for certain failures. Substitute values can be adopted for Engine Coolant Temperature (ECT) sensor signal, Throttle Position (TP) sensor signal, Mass Airflow (MAF) sensor signal, and oxygen sensor (HO2S) signal. See Fig. 1.
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1995 Volvo 850 Turbo Engine Troubleshooting With Codes
July 23rd, 2008 · No Comments
1995 Volvo 850 Engine Troubleshooting With Codes
July 21st, 2008 · No Comments
If no faults were found while performing procedures in the F - BASIC TESTING article, proceed with self-diagnostics. If no fault codes are present, proceed to the H - TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.). NOTE: All voltage tests should be performed using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in testing procedures.
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