DC20 - Check MAF Circuit Output

- Key "OFF".

- Reconnect Mass Air Flow (MAF) sensor.

- Breakout box installed, Powertrain Control Module (PCM) connected.

- Key "ON", engine running.

For Multiport Fuel Injection (MFI) vehicles:

- Measure voltage between test pin 14 and test pin 15 at the breakout box.

For Sequential Fuel Injection (SFI) vehicles:

- Measure voltage between test pin 50 and test pin 9 at the breakout box.

- Is voltage between 0.36 and 1.50 volts?

Yes -- Go to DC21. DC21 - Check For Other Diagnostic Trouble Codes

No -- Replace MAF sensor. Remove breakout box. Reconnect PCM. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)