Honda Civic Service Manual page 265

PGM-FISystem
(
(
(
DTC Troubleshooting (cont'dl
DTC P0117: ECT Sensor Circuit Low Voltage
1 . T u r n t h e i g n i t i o n s w i t c h O N ( l l ) .
2. Check the ECT with the scan tool.
ls 150'C (302'F)or higher (ot H-Limit in Honda
mode of PGM Tester) or 0 V indicated?
YES Go to step 3.
NO Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the ECT sensor and at the ECM. t
3. Disconnect the ECT sensor 2P connector.
4. Check the ECT with the scan tool.
ls 150'C (302"F)or higher (ot H-Limit in Honda
mode ot PGM Tester) or 0 V indicated?
YES-Go to step 5.
NO Replace the ECT sensor. !
5. Turn the ignition switch OFF.
6. Disconnect ECM connector B (24P).
1 1 - 5 8
\
7. Check for continuity between the ECT sensor 2P
connector terminal No. 1 and bodv oround.
ECT SENSOR 2P CONNECTOR
Wire side of female terminals
ls there continuity?
YES-Repair short in the wire between the ECM
( B 8 ) a n d t h e E C T s e n s o r . l
NO-Update the ECM if it does not have the latest
software,or substitute a known-good ECM, then
recheck {see page 11-6). lf the symptom/indication
goes away with a known-good EClvl, replace the
o r i g i n a l E C M . I