Operation CHARM: Car repair manuals for everyone.

HA12 - Check Injector Driver Signal



Requires standard non-powered 12 volt test lamp.

- Key "OFF".

- Breakout box installed.

- Connect Powertrain Control Module (PCM) to breakout box.

- For Multiport Fuel Injection (MFI):

- Connect test lamp between test pin 37 and test pin 58 at the breakout box.

- Connect test lamp between test pin 37 and 59 at the breakout box.

- For Sequential Fuel Injection (SFI):

- Connect test lamp between test pin 37 and the suspect injectors test pin at the breakout box.

- Crank or start engine.

NOTE: Properly operating systems will show a dim glow on the lamp.

- Is glow on lamp dim?

Yes -- Remove breakout box. Reconnect PCM. Follow instructions of the injector test equipment. Also refer to Ignition Section for other possible causes. After any servicing, Drive vehicle 5 miles/55 mph. Rerun Quick Test and Cylinder Balance test. Quick Test Appendix (Detailed Testing Instructions)

No -- No light/Bright light: Replace PCM. Remove breakout box. Drive vehicle 5 miles/55 mph. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)