EG–422 ENGINE – 2JZ-GE ENGINE TROUBLESHOOTING INSPECTION PROCEDURE (Only for California specification vehicles) HINT: If diagnostic trouble code "21" is output, check the main heated oxygen sensor (Fr) circuit. If diagnostic trouble code "28" is output, check the main heated oxygen sensor (Rr) circuit. 1 Check voltage between terminals HT1, HT2 of engine control module connector and body ground. ON SST ECM B 73, 72 HT1 HT2 BE6653 FI6890 P Connect SST (check harness "A"). See page EG–404) SST 09990–01000 C Measure voltage between terminals HT1, HT2 of engine control module connector and body ground. OK Voltage: 9 — 14 V NG OK Go to step 3 . 2 Check main heated oxygen sensor heater. P11484 2 1 P Disconnect main heated oxygen sensor connector. C Measure resistance between terminals 1 and 2 of main heated oxygen sensor connector. OK Resistance: 11 — 16 Ω at 20˚C (68˚F) OK NG Replace main heated oxygen sensor. Check and repair harness or connector between main relay and main heated oxygen sensor, main heated oxygen sensor and engine control module.