little confused on using a jumper to check engine codes...

[killer5.0]

i have a MIL light on my car (93) and i want to check for codes...the diagram shows multiple jumper wire it looks like but dont i just need to run a power jumper to the self diagnostic harness? or do i need to hook up a few connections? thanks

 

[liljoe07]

The jumper just goes from the STI to SIGRTN. Then count the flashes from the MIL on the dash.
View attachment 224771

 

[Mustang5L5]

That's all you need. One jumper wire. The other wires are for 86-88's that don't have a CEL and need a bulb to blink

It's very easy.

I vbought this little reader a while back. It displays the codes numerically, so no more counting blinks
Digital Ford Code Reader (3145)

 

[killer5.0]

okay..i got it to work...just got code 11 which means all is okay according to my research..also i just used a paper clip

 

[Mustang5L5]

Well technically you want to get three code 11's.

Code 11, followed by a 2nd code 11...when you get the the pause, then you need to start the engine. The revs should climb up to around 2000RPM, come down and then the light will blink once. This is your signal to blip the throttle. After the blip, the engine running codes will be displayed.

 

[liljoe07]

Dont have to hit the throttle. Just install the jumper or paper clip. Then start the engine. It may take a few minutes for the ECM to run its tests. Then the codes will flash.

 

[killer5.0]

okay ill do it again in a few min and see what i get

 

[killer5.0]

ok...installed jumper and started car...blink, blink...quick pause...blink,blink...engine rose to almost 2000rpm...went down (almost stalled) back up and down (almost stalled again) back up...slowly came down to 1000rpm blink, blink, 2-3sec pause blink...2-3sec pause..blink blink...2-3 sec pause blink...and that was it.

 

[joel5.0]

That would be code 21 or ECT sensor out of range.... IOW, too cold. You need to first make sure the engine coolant temp is above 160° and then run the KOER self test. LUK

 

[killer5.0]

okay..yeah its pretty chilly here today (40) guess ill have to let it warm up then give her a shot...prob wont be able to until tomorrow or monday now but i will post up results...thanks

 

[killer5.0]

could i have just done something...i let the car idle for like 10 min...temp was right about 160 shut it off but had the key in the on position...inserted the paper clip...went to start the car...idle up to 2k then stalled...keeps stalling unless i keep my foot on the gas slightly...i am low on fuel at the moment (on E) but i dont think thats an issue since it was idling fine do you? i have to go get some fuel tomorrow.