DTC P0135: HO2S HEATER (FRONT) CIRCUIT MALFUNCTION Kia Sephia I рестайлинг

Heated Oxygen Sensor (HO2S) heater (front) circuit malfunction code may be set by

1. HO2S sensor heater (front) malfunction.
2. Open or short circuit between ignition switch and HO2S sensor terminal No. 3.
3. Open or short circuit between PCM connector C254 terminal No. 7 and HO2S sensor terminal No. 2.

1. Check HO2S and PCM connections. Repair as needed. Go to next step.
2. Check PCM pin voltage at connector C254 terminal No. 7. See «PIN VOLTAGE CHARTS»(ref-25101) article. If voltage is okay, go to step 6). If voltage is out of specification go to next step.
3. Disconnect HO2S (front) connector. Check for battery voltage at HO2S sensor connector terminal No. 3 (1.6L) or No. 2 (1.8L). If continuity exists, go to next step. If continuity does not exist, repair wiring.
4. Check continuity between PCM connector C254 terminal No. 7 and HO2S sensor connector terminal No. 2 (1.6L) or No. 4 (1.8L). If continuity exists, go to next step. If continuity does not exist, repair wiring.
5. Check continuity between HO2S sensor connector terminals No. 2 and 3 (1.6L) or terminals No. 2 and 4 (1.8L). If continuity exists, go to next step. If continuity does not exist, replace HO2S.
6. Clear code. Recheck codes. If code returns, replace PCM. If code does not return, problem is intermittent.