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DC19 - Check MAF Circuit Output



- Key "OFF".

- Reconnect Mass Air Flow (MAF) sensor.

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

- Key "ON", engine running.

- Measure voltage between test pin 50 at the breakout box and negative battery post.

- Is voltage between 0.36 and 1.50 volts?

Yes -- Go to DC20. DC20 - Check MAF Circuit Output

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