IAC solenoid wiring

[cvanarsdall]

I just bought a 1990 bronco ii and i found the wires off the IAC solenoid taped together and burnt up. Does anyone know where the wires are routed? 

 

[miesk5]

yo C,

WELCOME!

What Engine is in your Bronco II?

if 2.9

• Turn the ignition switch to the  OFF position.
• Disengage the wiring harness connector from the IAC valve .
• Using an ohmmeter, measure the resistance between the terminals of the valve.NOTE: Due to the diode in the solenoid, place the ohmmeter positive lead on the  VPWR terminal and the negative lead on the  ISC terminal.
  
• If the resistance is not 7–13 ohms, replace the IAC valve.
• Turn the ignition switch to the  OFF position.
• Disengage the wiring harness connector from the IAC valve .
• Using an ohmmeter, measure the resistance between the terminals of the valve.NOTE: Due to the diode in the solenoid, place the ohmmeter positive lead on the  VPWR terminal and the negative lead on the  ISC terminal.
  
  
• Turn the ignition switch to the  OFF position.
• Disengage the wiring harness connector from the IAC valve .
• Using an ohmmeter, measure the resistance between the terminals of the valve.NOTE: Due to the diode in the solenoid, place the ohmmeter positive lead on the  VPWR terminal and the negative lead on the  ISC terminal.
  
• If the resistance is not 7–13 ohms, replace the IAC valve.~.

In this diagram, 71 is the pin in Fords Obsolete test box; in wiring diagrams It is RED & it is VPWR Vehicle Power (Battery Voltage)

ISC wire is Gray/White & goes to Pin 21 in EEC (aka computer, etc.)

according to Chilton

Overview & Testing; "First let me say this little thing has many names. But they all talk about the same item under the hood. Here all the names I’ve had the torture of learning throughout the years: Idle Air Bypass •Idle Air Control •Idle Speed Control •Throttle Bypass Air •Idle Bypass •Inlet Air Controller •Inlet Air Bypass •Intake Air Bypass •Intake Air Control..."

Source: by Ryan M (Fireguy50) at http://web.archive.org/web/20101224145410/http://fordfuelinjection.com/index.php?p=39

Consider Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; & Ford Fuel Injection and Electronic Engine Control: How to Understand, Service, and Modify All Ford-Lincoln-Mercury Cars and Light Trucks, 1980 to 1987 by Charles Probst

avail @ BARNES & NOBLE, AMAZON, E BAY, ETC.

 

[miesk5]

yo,

VPWR - Vehicle Power (Battery Voltage) is RED

90 Bronco !! WIRING DIARAM SHOWING IAC etc.pdf]