How-To: retrieve trouble codes- OBDI
Certain things I remember about the hook up, I'm sure Sean will be along to help. You have to use an analogue voltmeter not a digital. Positive lead to batt pos. negative lead to the second from left with the four pin row at bottom. Jumper the little dangling connector to the top right pin. Turn key to on and count the needle sweeps just as Sean explained.
Last edited by Good old Bill; Oct 27, 2008 at 05:12 PM.
If your truck has a check engine light then you don't need to hook up the voltmeter, you just count the flashes. If the bulb is burned out and you don't feel like changing it, then you can use the voltmeter to read the codes. Turn on the ignition key and make sure the check engine light comes on. If you're sure you have the hookups right and they are making good contact and the computer still won't go into diagnostic mode then that usually means the computer is fried.
My truck usually relearns my driving style after about 50 miles of driving.
My truck usually relearns my driving style after about 50 miles of driving.
If your check engine light doesn't work you can still get the codes by using a voltmeter as shown in the diagram. You should change the bulb so it does work. If you recently got this truck then I have seen people remove the bulb because the light was on.
Sean - I've got an '89 F-150, 4WD, straight 6, 300. The picture above is clear enough, and I found the STO and STI . . . but the port on the STO that you show jumping to the STI is like a dry well. Any reason why Ford would leave that port un-wired? Any work around possible?
Thanks -
cz
Thanks -
cz
I've never seen one that didn't have the wire. Maybe it came out or broke off. Check the harness to see if there's a loose wire. Make sure you have the correct spot in the plug because some others aren't used.
us guys with digital mileage can do this to scan for trouble codes as of a few other things...
http://http://www.obd-codes.com/trouble_codes/ford/
The above site lists Ford trouble codes. You might find it useful if you use the following diagnostic trick:
With the key OFF, push (and hold down) the SELECT/RESET button on your odometer.
Start the vehicle while still holding the button. Continue to hold it down, until all of your gauges jump up to their maximum, and then return to normal.
When you see "bulb" in the digital odometer readout, let off the button. This is the gauge test mode.
Some of the things you can view on your odometer screen are:
Digital speedometer (mph)
Digital tachometer (RPM)
Digital speedometer (kph)
Battery Voltage
Engine Temperature
Plus, you can also view any
TCs stored in the computer!
http://http://www.obd-codes.com/trouble_codes/ford/
The above site lists Ford trouble codes. You might find it useful if you use the following diagnostic trick:
With the key OFF, push (and hold down) the SELECT/RESET button on your odometer.
Start the vehicle while still holding the button. Continue to hold it down, until all of your gauges jump up to their maximum, and then return to normal.
When you see "bulb" in the digital odometer readout, let off the button. This is the gauge test mode.
Some of the things you can view on your odometer screen are:
Digital speedometer (mph)
Digital tachometer (RPM)
Digital speedometer (kph)
Battery Voltage
Engine Temperature
Plus, you can also view any
TCs stored in the computer!


