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Global OBDII Diagnostics
O2 MONITOR TEST
✓The O2 Monitor Test is NOT AN
✓If vehicle communicates using a Controller Area Network (CAN), O2 Monitor tests are NOT supported by vehicle. A message is displayed. See Diagnostic Monitor Test to see O2 Monitor data.
| OBDII regulations require applicable vehicles monitor and test oxygen (O2) |
| sensors to determine problems related to fuel and emissions. The O2 Monitor |
| Test allows retrieval of completed O2 sensors monitor test results. |
| O2 sensors are located before (upstream) and after (downstream) catalyst(s). |
| Sensors are named (xy) for their position to both cylinder banks and catalysts. |
| • The O2 sensor for cylinder bank 1 has prefix 1y while O2 sensor for cylinder |
| bank 2 has prefix 2y. |
4 4 | • The O2 sensor upstream of catalyst (closest to engine) has suffix x1 while |
O2 sensor downstream of catalyst has suffix x2. If vehicle contains more |
catalysts, O2 sensor downstream of second catalyst has suffix x3 and O2 sensor downstream of next catalyst has suffix x4.
• For example, O2S21 is upstream O2 sensor for cylinder bank 2.
The following O2 sensor tests are available:
1)Rich to Lean sensor threshold voltage
2)Lean to Rich sensor threshold voltage
3)Low sensor voltage for switch time
4)High sensor voltage for switch time
5)Rich to Lean sensor switch time
6)Lean to Rich sensor switch time
7)Minimum sensor voltage test cycle
8)Maximum sensor voltage test cycle
9)Time between sensor transitions
10)Sensor Period
Select O2 Monitor Test from OBDII | OBDII Function List | ? |
Function List and press ENTER. | ||
| ` 7)O2 Monitor Test | ] |
| 8)Diag Mon Test | [ |
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