no spark from coil

I was looking though my the FORD tech CD and found out how to pull the codes from the PCM. After hooking it up, I went to observe the check engine light and it never comes on. I then tried the instructions for using an analog VOM and when I turn the key on, I get 12 volts continuously instead of the bouncing meter I would have expected to display the codes. Also, I noticed that after I tried this test, the coil got very hot. This is sounding more and more like a wiring problem within the harness, but I don't know where to start diagnostics on that.

Reply to
SPMcClellan
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very hot. This is sounding more and more like a wiring

My Bad... there are two connectors there that are the same shape and both have yellow/green wires. I was on the wrong yellow/green. It was to the tachometer (if I had one). I found the correct yellow/green and still no check engine light, but when I try the VOM, then I get a solid 12 volts when I turn the ignition on. I am assuming this means there are no codes stored.

Reply to
SPMcClellan

in article snipped-for-privacy@j22g2000hsf.googlegroups.com, snipped-for-privacy@gmail.com at snipped-for-privacy@gmail.com wrote on 7/5/08 3:31 PM:

burn it ...

Reply to
Alan B. Mac Farlane

Hey here,

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Andy Deil

Reply to
ADdiy55

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lgot very hot. This is sounding more and more like a wiring

It sounds like your check engine light isn't coming on at all, even for a key on self check. I would check the "EGI" fuse located in a small box called the Main Fuse Link Panel near the left strut tower in the engine compartment. It is a 15 amp fuse, the box cover should label it as "EGI". Also check the "Main Relay" located near this fuse box in another relay box. You won't have crank signal CKP, fuel pressure, fuel injector operation, etc, and I suspect the ECM will not be able to turn on the check engine light without power at either of these two points.

Toyota MDT in MO

Reply to
Comboverfish

I wanted also to mention that you are seeing ignition coil B+ with a test light because it comes from the ign key through another fuse. It is not toggling on/off since there is no ignition primary control, likely due to the blown EGI fuse or open circuit, resulting in an offline ECM and missing sensors such as the CKP, as theorized in my last post.

Toyota MDT in MO

Reply to
Comboverfish

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