Honda Civic Service Manual page 273

PGM-FISystem
a
DTC Troubleshooting (cont'dl
10. Check for continuity between the secondary HO2S
(Sensor 2) 4P connector terminal No. 2 and body
grou nd.
SECONDARY H02S
ISENSOR 2) 4P CONNECTOR
Terminal side of male terminals
ls there continuity?
YES-Repair shon in the wire between the ECM
(E2) and the secondary HO2S (Sensor 2). t
NO Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
o r i g i n a l E C M . I |
1 1 - 6 6
DTC P0138: Secondary HO2S (Sensor 2)
Circuit High Voltage
1 . R e s e t t h e E C M { s e e p a g e ' 1 1 - 4 ) .
2. Startthe engine. Hold the engine at 3,000 rpm with
no load (in neutral) until the radiator fan comes on.
3. Check the secondary HO2S (Sensor 2) output
voltage at 3,000 rpm with the scan tool.
ls thete 1.0 V or morc?
YES Go to step 4.
NO-lntermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the secondary HO2S (Sensor 2) and at the ECM.I
4. Turn the ignition switch OFF.
5. Disconnect the secondary HO2S (Sensor 2) 4P
connector.
Connect secondary H02S (Sensor 2) 4P connector
t e r m i n a l s N o . 1 a n d N o . 2 w i t h a j u m p e r w i r e .
SECONDARY HO2S
{SENSOR 2) 4P CONNECTOR
JUMPER WIRE
SG3 (PNKI
SHO25 (WHT/RED)
T e r m i n a l s i d e o J m a l e t e r m i n a l s
7 . 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 ) .