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I have a 95 Ford Taurus GL, and for some reason it will not get 12 volts to the fuel injectors. Actually it appears to be getting no power at all. If any one has any ideas or a wiring diagram for the injectors specifically I would greatly appreciate it. I do know that the wire from the CCRM to the power for the fuel injectors is working. It has next to no resistance when measuring it. However I did just remember that the CCRM only put out about 1.4-1.7 Volts when I was testing it while it was plugged in. In need of serious help please.
 

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NEVER check power supply circuits with a voltmeter. Always use a test light!!

Injectors are powered via the VPWR circuit.

For a test, run a wire from the battery to the hot side of the injectors and see if the engine starts / runs.
 

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Could you please explain what the VPWR circuit is? And when doing this test, will I need to be running a ground as well as a power, or just straight power to the injectors? In doing this, Isn't it also possible that I will ruin the Injector as Injectors will generally pulse when gas is needed as opposed to constantly having power? Thank you for the help so far. I'm new to ford and just starting to understand and get into the game
 

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VPWR (stands for Vehicle Power) circuit is powered up via the EEC power relay inside the IRCM/CCRM whenever the key is in start or run positions. VPWR circuit supplies 12 V to various actuators under the hood like injectors, IAC, various solenoids, etc. VPWR wires are typically red. All actuators are switched on by being grounded by the PCM.

With key in start or run, injectors have constant 12 V applied to one side. PCM grounds injectors to open them.
 

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Discussion Starter #5
VPWR (stands for Vehicle Power) circuit is powered up via the EEC power relay inside the IRCM/CCRM whenever the key is in start or run positions. VPWR circuit supplies 12 V to various actuators under the hood like injectors, IAC, various solenoids, etc. VPWR wires are typically red. All actuators are switched on by being grounded by the PCM.

With key in start or run, injectors have constant 12 V applied to one side. PCM grounds injectors to open them.
So in theory, If I am understanding this right, I should only have to run power to the injectors, and they should already be grounded through the pcm? And if I am making sense of this, if the Injectors do work when doing this, then the PCM or the CCRM are bad, and one of them needs to be replaced? Is there a way to tell which one it is?
 

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Easy place to check for VPWR is at the IAC connector. Remove the IAC connector and run a test light from ground to one or the other terminals on the IAC connector with the key in RUN. One terminal will not light the light (the PCM PWM control signal) and the other terminal should light up the test light. If the test light lights up at 1 terminal, the CCRM/IRCM is supplying power to the VPWR circuit. Now pull the connector off a convenient injector. With key still on, do the same test as on the IAC. If light lights up at 1 terminal, at least the injector is powered. If no light, try another injector. If no light, the injector 12 V feed from the CCRM has an open circuit.
 
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