- Joined
- June 3, 2003
- Messages
- 3,252
- Reaction score
- 46
- City, State
- Austin, TX
- Year, Model & Trim Level
- OBD-1 Kenobi
Hello all. First off, I would like to thank all of you who have contributed to this site, to help others, and for others to find very useful information. Now, I feel like I can share something with the Explorer community. Here is a check engine light mod I've done, and have had for about a year now. This is especially useful for those of you that need to pull a code, for whatever reason, without having to use a jumper wire, opening your hood, or even leaving the driver seat. The design of the mod is very simple in nature, but I haven't seen anywhere on here where someone has done it, so I want to be the first
. Here is the procedure I have taken. Please note: This mod will only work on OBD-1 PCM systems. Limited to the 1991-1994 explorers, and some 1995 ('95 owners, double check before continuing with this mod.) Also, I, Russell Darnell, am not responsible for any damage/injuries sustained, if any, with this mod. You do this mod at your own risk(Have to cover my butt guys
)
Objective:
To access EEC IV computer codes without using a jumper wire, opening the hood, or using a scanner tool. The idea is to use the Malfunction Indicator Light (check engine light) to read the trouble codes stored in the PCM. In turn, after doing this mod, you will be able to sit in the driver seat, and watch the CEL and read the codes from there.
Materials
Here is a list of materials and tools you will need for this mod:
1)Some sort of toggle switch. This is pretty much up to you, what kind you want. You will see what switch I used.
2)16-18 guage wire. Depending on location of the switch, will, of course, depend on the amount of wire you need.
3)Wire splicer. Again, lots of variety. Just something that will splice the above wire into wire in the wiring harness of the PCM.
4)Wire crimpers. DUH.
5)Drill. (Optional). Depending on your application, you will need to drill a hole for the toggle switch.
That about covers the materials.
Time for installation
An hour tops, even for the mechanically impaired.
Procedure
1) Ok, now for the fun stuff. As always, disconnect the negitive terminal on the battery for safety. Then, locate the diagnostic test terminal, near the blower fan, on the passenger side in the engine compartment:
Normally, the two pins that are circled are the ones you would connect the jumper wire too. What this mod will do, is install a permenant jumper wire, with a break(toggle switch) in it so the user(you) will be able to put the PCM in diagnostic mode, whenever the user(you) needs to pull a code(s).
FYI, the single grey pin in the upper left of the picture is your Self Test Input pin. And the other pin on the black 6 Pin terminal, is the Signal Return Pin(Pin 2). For simple code pulling, and for this mod, these are the only two you need to worry about.
Next, write(or remember, doesn't matter) the wire that is going to each pin. Wires might be different for each vehicle, so I won't specify a certain color wire for each pin. These two wires will be found in the passenger kick panel, where the PCM is located. Just remember what the wires are.
2)Find a location for your toggle switch. Anywhere you would like it, but remember. You don't want to be going down the road, and accidently push the button, and have the computer go into diagnostics mode. That will be bad for you! I chose my glove box. It's hidden, not able to be triggered, and out of my way until I need it.
Note: Mounting the switch to this location did require me to remove the glove box door. See your repair manual for instructions.
That little hole was perfect for that toggle switch. I did have to remove the glove box, and drill out the plastic behind it for the wires, but no big deal.
Next, install your wires to the contacts on the back of the switch, via connectors or soldering. Then install the switch wherever you like, and run the wires to the passenger kick panel.
3) Remove the plastic kick panel to expose the PCM.
I found it worked best to remove the PCM from the bracket, and then remove the wiring harness from the PCM, to locate and splice into the PCM wires. This is where you need to find the two wires that you wrote down earlier from the diagnostics test terminal. Once the two wires are found, splice your two new wires into the diagnostics test teminal wires. Therefore, creating the permenant jumper wire. Make sure the splice is solid, and firm, then reinstall your wiring harness, PCM, and kick panel. To make sure everything is working properly, get a continuinty meter(Multimeter)and turn the switch on(Battery is still disconnected). The go inside the engine compartment, and stick the multimeter pins into the above cirlced pins(1st picture). There should be continuinty between those two pins. Now turn the switch off, and repeat. There should now be no continuinty between the two pins. If you yeild these results, your done!
I hope this mod will help those of you that need it. I know, for me, it's a lot easier to pull codes. Just the other day, I was driving to school, and my CEL came on. So, when I reached the school parking lot, I pulled my codes right there. Turns out my air intake came loose from my throttle body, causing unmetered air into the engine. But non-the-less, it worked. So, hope all of you enjoyed this mod, and hope I helped some people out. If you have any questions, post here, or email me, at Nghtrdrtbone05@aol.com. Thanks!
-Russell Darnell
-Blue Banidt
. Here is the procedure I have taken. Please note: This mod will only work on OBD-1 PCM systems. Limited to the 1991-1994 explorers, and some 1995 ('95 owners, double check before continuing with this mod.) Also, I, Russell Darnell, am not responsible for any damage/injuries sustained, if any, with this mod. You do this mod at your own risk(Have to cover my butt guys) Objective:
To access EEC IV computer codes without using a jumper wire, opening the hood, or using a scanner tool. The idea is to use the Malfunction Indicator Light (check engine light) to read the trouble codes stored in the PCM. In turn, after doing this mod, you will be able to sit in the driver seat, and watch the CEL and read the codes from there.
Materials
Here is a list of materials and tools you will need for this mod:
1)Some sort of toggle switch. This is pretty much up to you, what kind you want. You will see what switch I used.
2)16-18 guage wire. Depending on location of the switch, will, of course, depend on the amount of wire you need.
3)Wire splicer. Again, lots of variety. Just something that will splice the above wire into wire in the wiring harness of the PCM.
4)Wire crimpers. DUH.
5)Drill. (Optional). Depending on your application, you will need to drill a hole for the toggle switch.
That about covers the materials.
Time for installation
An hour tops, even for the mechanically impaired.
Procedure
1) Ok, now for the fun stuff. As always, disconnect the negitive terminal on the battery for safety. Then, locate the diagnostic test terminal, near the blower fan, on the passenger side in the engine compartment:
Normally, the two pins that are circled are the ones you would connect the jumper wire too. What this mod will do, is install a permenant jumper wire, with a break(toggle switch) in it so the user(you) will be able to put the PCM in diagnostic mode, whenever the user(you) needs to pull a code(s).
FYI, the single grey pin in the upper left of the picture is your Self Test Input pin. And the other pin on the black 6 Pin terminal, is the Signal Return Pin(Pin 2). For simple code pulling, and for this mod, these are the only two you need to worry about.
Next, write(or remember, doesn't matter) the wire that is going to each pin. Wires might be different for each vehicle, so I won't specify a certain color wire for each pin. These two wires will be found in the passenger kick panel, where the PCM is located. Just remember what the wires are.
2)Find a location for your toggle switch. Anywhere you would like it, but remember. You don't want to be going down the road, and accidently push the button, and have the computer go into diagnostics mode. That will be bad for you! I chose my glove box. It's hidden, not able to be triggered, and out of my way until I need it.
Note: Mounting the switch to this location did require me to remove the glove box door. See your repair manual for instructions.
That little hole was perfect for that toggle switch. I did have to remove the glove box, and drill out the plastic behind it for the wires, but no big deal.
Next, install your wires to the contacts on the back of the switch, via connectors or soldering. Then install the switch wherever you like, and run the wires to the passenger kick panel.
3) Remove the plastic kick panel to expose the PCM.
I found it worked best to remove the PCM from the bracket, and then remove the wiring harness from the PCM, to locate and splice into the PCM wires. This is where you need to find the two wires that you wrote down earlier from the diagnostics test terminal. Once the two wires are found, splice your two new wires into the diagnostics test teminal wires. Therefore, creating the permenant jumper wire. Make sure the splice is solid, and firm, then reinstall your wiring harness, PCM, and kick panel. To make sure everything is working properly, get a continuinty meter(Multimeter)and turn the switch on(Battery is still disconnected). The go inside the engine compartment, and stick the multimeter pins into the above cirlced pins(1st picture). There should be continuinty between those two pins. Now turn the switch off, and repeat. There should now be no continuinty between the two pins. If you yeild these results, your done!
I hope this mod will help those of you that need it. I know, for me, it's a lot easier to pull codes. Just the other day, I was driving to school, and my CEL came on. So, when I reached the school parking lot, I pulled my codes right there. Turns out my air intake came loose from my throttle body, causing unmetered air into the engine. But non-the-less, it worked. So, hope all of you enjoyed this mod, and hope I helped some people out. If you have any questions, post here, or email me, at Nghtrdrtbone05@aol.com. Thanks!
-Russell Darnell
-Blue Banidt
