DTC P0117-P0118: ENGINE COOLANT TEMPERATURE (ECT) SENSOR CIRCUIT Saab 9-5 I

1. Disconnect ECT sensor connector. see scheme 1, see scheme 3 or see scheme 4 for ECT sensor and ECM locations. Connect SST 86 11 857 test light see scheme 9 or equivalent between positive battery terminal and ECT sensor connector terminal No. 2 (Black wire). see scheme 13 If test light illuminates, go to next step. If test light does not illuminate, check for faulty circuit between ECT sensor connector terminal No. 2 and ground splice connector (Black wire) located about 3" from ECM connector cable tie. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-3491) article. Repair as necessary and go to step 4.
2. Connect TECH 2 scan tool to Data Link Connector (DLC). Turn ignition on. Check engine coolant temperature reading. Scan tool display should be -40°F (-40°C). If readings are to specification, go to next step. If readings are not to specification, check for faulty circuit between ECT sensor connector terminal No. 1 and ECM connector terminal No. 39 (White/Green wire). see scheme 11for ECM terminal identification. Repair as necessary and go to step 4.
3. Connect a jumper wire between ECT sensor connector terminals No. 1 and 2. Reading on scan tool should now be about 302-320°F (150-160 °C). If reading is as specified, replace ECT sensor. See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR»(ref-2997-S00940252562000041700000) under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION article. If reading is not as specified, check for faulty circuit between ECT sensor connector terminal No. 1 and ECM connector terminal No. 39 (White/Green wire). Repair as necessary and go to next step.
4. If sent to this test procedure from DTC P0125, go to next step. Otherwise, use scan tool to clear DTCs. Drive vehicle for 5 minutes under varying loads and engine RPM. Recheck for any stored DTCs. If DTCs are present, substitute known good ECM and retest system. See «ENGINE CONTROL MODULE (ECM)»(ref-2997-S17585372472000041700000) under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION article.
5. Ensure that both intake air- and coolant temperatures exceed 50°F (10°C). Start engine and allow it to idle for at least 4 minutes. Check status of DTCs with scan tool. If OK is displayed, use scan tool to clear all system DTCs. If NOT READY is displayed, back up to INITIATING DIAGNOSTICS on scan tool and retest. If DTCs are still displayed, problem has not been corrected.

Scheme 12