went to advance to scan my 95 f150 and the guy told me they can not scan obd1 codes.am i going to have to take it to a shop to have it scanned?i priced scanners off the internet(to rich for my budget)i think i remember reading other post that talked about getting them off of your digital odometer but i cant find it in the search.can someone tell me how to do it?

 

Here's how to read the codes using your check engine light (CEL). I'll describe the basic KOEO (Key On Engine Off) test:

First you'll need a piece of wire of some sorts to connect two terminals. You'll see what I mean.

With the engine off, pop the hood and find the EEC connecter, located on the left-hand fender closer to the firewall at the top edge of the engine compartment. It is a black connector not connected to anything, but it is clipped in a protective plastic piece. Unclip that connector (has 6 terminals) from the protective plastic piece.

Next to that connector is a small gray single connector in the same protective plastic piece. Unclip that as well.

Now looking at the larger connector with 6 terminals, oriented so that the 4-terminal row is facing down and 2-terminal row is facing up, stick the connecting wire into the top right terminal (right terminal of the 2-terminal row, oriented like I described). Stick the other end of the wire into the single gray connector.

Now turn the key to run (not to start) and read the codes. They will flash fairly quickly so get ready to write. How do you read them? I'll use 212 as an example: it will flash once, followed by a 1/2 second pause, then flash again to indicate "2", then a 2 second pause, then it will flash once to indicate "1", then a 2 second pause, then it will flash once with a 1/2 second pause, then again to indicate "2". There will be a 4 second pause in between codes.

When the KOEO codes are complete, there will be a 6 second pause, then a single flash, followed by a 6 second pause. Following the KOEO codes there will be "Continuous Codes" displayed in the same way as above.

If you want to clear the codes, simply unplug the jumper wire while the test is going on.

So that's how you do the basic KOEO test to get your codes.

 

great info thanks lucky37.......that sounds easy.

 

I Tried It Today And What I Am Getting;((121))..closed Throttle Voltage Higher Or Lower Than Expected.((122)) &((123))...tp Sensor Circuit Below Max Voltage.((124)) That My Manual Does Not List.((211))...pip Circuit Fault....(keep In Mind I Am Learning As I Go)......im Guessing The Tps Is Bad?as For The ((121)) & ((211)) I Have No Idea How To Resolve These....will Any Of These Cause The Truck To Shift Down At 50 Mph? Or Is It Just Causing My Idle Problem?sorry For All The Questions

 

From http://www.freeautomechanic.com/diag...blecodes7.html

121 (O,R,M) Throttle Position (TP) sensor out of range - TPS
122 (O,M) TP low (possibly grounded or open circuit) - TPS
123 (O,M) TP is/was high or short to power - TPS
124 (M) TP voltage was higher than expected - Fuel control

211 (M) Ignition PIP signal was erratic or missing - Ignition Systems

I would think the 211 code is related to your idle problem.

Not sure about the downshifting, unless the computer watches the rate of change of the throttle to anticipate downshifting??? If so, then perhaps with the TPS flaky, the computer is getting some false feedback and reacting.

Don't worry about the questions - the only dumb ones you'll ever ask are the ones you already know the answer to. And, we're all learning as we go :-)

 

Thanks Wde3477

 

i have been starting the truck every other day until i can correct the problems.well today i started it as usual and let it run.when i went back out to shut it down the idle sounded steady.so i decided to drive it around.it drove strong and shifted fine?????no engine light or anything.....im at a loss as to what is going on with this truck.any ideas?

 

Given the codes you were getting, I'd say the chances are better than average the problem will be back. Perhaps the electrical gremlins weren't ready for you today :-)

But then again, there's always hope .....

 

Unlike ppl vehicles don't heal themselves.. I reccomend a new TPS sensor and cleaning the throttle body, just from the codes.

 

so true they will be back.lol.........i looked at the tps..is there any easy way to get to it?(or what i think is it).looks to be directly under the intake where hose meets metal..thanks for the help guys