Huge wiring problem... Cluster and Fuel pump
12-23-08, 03:01 AM
#1
Huge wiring problem... Cluster and Fuel pump
First off i am not a wiring genius, so please have patience with me on this post.
Beginning of story. Well i got my UIM put together today and everything was starting to come together after two years of the car not running. Anyways i turned the key to the on position, everything started up nicely (not car just electronics), pfc on and commander is displaying, but then the water temp is reading unconnected (irrelevant to this problem actually)
Anyways I went to go check it out, notice a fuel smell, look down and something is leaking fuel on the UIM, arrrgghh is just put it back together!! Well time to take it off and figure this out. Anyways Got rats nest removed, started diggin around and then decided to check the fuel pump by doing the test on page F-100 of the workshop manual, anyways i tried to jump the fuel pump and this is where my story begins...
First off i know it was working before i tried to find the leak because there was pressure and fuel in the line. Anyways I am in the process of checking the fuel pump and turn the key to the on position obviously. Anyways i am not getting anything while jumping the fuel pump from the diagnostics connector. In the transition of moving some wires around i accidentally touch the ground wire to the positive on the battery, BIG no no. Anyways i got the average spark and pulled it back immediately.
I went to go look in my car a couple of minutes later and notice some stuff is acting up on the interior. So here are my symptoms
1. guage cluster lights up, but does not register anything. No odometer miles, fuel level indicator is way above full (only half full when i started and it was reading correctly), oil pressure off the charts also, and i have no coolant in my system so the buzzer was ringing at me constantly, and now it is dead. Everything lights up but i know the cluster bulbs are something completely different than the actual cluster stuff itself. And now for the scariest part, my powerfc commander is out. Completely blank and i am really scared about this one actually ( is there any way a quick short like this would actually blow it?).
2. Now there is also no response on the fuel pump. I tried it and there is no engagement when the power wire to it is jumped from the diagnostics connector. So now my commander is out, my fuel system, and my guage cluster..... life sucks. So i start trying to figure this thing out. Here is my only lead i have on it so far to be honest. It seems like everything fuel related went dead, possibly through the computer but i don't think that would destroy my fuel pump turning on or my cluster to go out. I do have one clue that i am onto but i have no idea what to make of it. When i turn my key from the on position to the accessory halfway between my oil pressure guage move slightly, my commander lights up and goes to the start screen for a split second, and something weird with the relays happens, here's what it is.
when i turn it to the on position there is no clicking on the fuel pump relay, but when it is in this transition between key on and key accessory the relays click on (or maybe off) for the fuel pump and the other one right next to it. That is also when my p-fc tries to power up. I am not sure what is going on here but it seems like half of my system just went and switched modes on me and is trying to power up at the wrong time and stays off when the key is on.... Completely weird. Many other things are working on the on position (lights, radio, etc etc). Anyways i am really stumped right now.
Did i blow my dash, computer, fuel system, or all of the above? It doesn't seem like it but man am i confused. I don't even know where to start with this one any help would be appreciated. I am just praying right now that my computer isn't fried along with my instrument cluster. I have this optimistic feeling it isn't though since my commander tries to power up for a split second. (have shorted out between a screwdriver between negative and positive terminals several times while working on the car but have never seen any realy effects) BTW i switched out to a stock ecu and no difference, same stuff, and i find it more weird even that i have all the block off plates and the known working stock ecu isn't even throwing a code (not all warning lights light up when key is turned to on now either). This is honestly one of the most mind boggling things i have encountered with this car, but maybe that's just because i am not an electrician of any sort. Anyways electrician geniuses here's one to test you all out.
--Thanks in advance
Beginning of story. Well i got my UIM put together today and everything was starting to come together after two years of the car not running. Anyways i turned the key to the on position, everything started up nicely (not car just electronics), pfc on and commander is displaying, but then the water temp is reading unconnected (irrelevant to this problem actually)
Anyways I went to go check it out, notice a fuel smell, look down and something is leaking fuel on the UIM, arrrgghh is just put it back together!! Well time to take it off and figure this out. Anyways Got rats nest removed, started diggin around and then decided to check the fuel pump by doing the test on page F-100 of the workshop manual, anyways i tried to jump the fuel pump and this is where my story begins...
First off i know it was working before i tried to find the leak because there was pressure and fuel in the line. Anyways I am in the process of checking the fuel pump and turn the key to the on position obviously. Anyways i am not getting anything while jumping the fuel pump from the diagnostics connector. In the transition of moving some wires around i accidentally touch the ground wire to the positive on the battery, BIG no no. Anyways i got the average spark and pulled it back immediately.
I went to go look in my car a couple of minutes later and notice some stuff is acting up on the interior. So here are my symptoms
1. guage cluster lights up, but does not register anything. No odometer miles, fuel level indicator is way above full (only half full when i started and it was reading correctly), oil pressure off the charts also, and i have no coolant in my system so the buzzer was ringing at me constantly, and now it is dead. Everything lights up but i know the cluster bulbs are something completely different than the actual cluster stuff itself. And now for the scariest part, my powerfc commander is out. Completely blank and i am really scared about this one actually ( is there any way a quick short like this would actually blow it?).
2. Now there is also no response on the fuel pump. I tried it and there is no engagement when the power wire to it is jumped from the diagnostics connector. So now my commander is out, my fuel system, and my guage cluster..... life sucks. So i start trying to figure this thing out. Here is my only lead i have on it so far to be honest. It seems like everything fuel related went dead, possibly through the computer but i don't think that would destroy my fuel pump turning on or my cluster to go out. I do have one clue that i am onto but i have no idea what to make of it. When i turn my key from the on position to the accessory halfway between my oil pressure guage move slightly, my commander lights up and goes to the start screen for a split second, and something weird with the relays happens, here's what it is.
when i turn it to the on position there is no clicking on the fuel pump relay, but when it is in this transition between key on and key accessory the relays click on (or maybe off) for the fuel pump and the other one right next to it. That is also when my p-fc tries to power up. I am not sure what is going on here but it seems like half of my system just went and switched modes on me and is trying to power up at the wrong time and stays off when the key is on.... Completely weird. Many other things are working on the on position (lights, radio, etc etc). Anyways i am really stumped right now.
Did i blow my dash, computer, fuel system, or all of the above? It doesn't seem like it but man am i confused. I don't even know where to start with this one any help would be appreciated. I am just praying right now that my computer isn't fried along with my instrument cluster. I have this optimistic feeling it isn't though since my commander tries to power up for a split second. (have shorted out between a screwdriver between negative and positive terminals several times while working on the car but have never seen any realy effects) BTW i switched out to a stock ecu and no difference, same stuff, and i find it more weird even that i have all the block off plates and the known working stock ecu isn't even throwing a code (not all warning lights light up when key is turned to on now either). This is honestly one of the most mind boggling things i have encountered with this car, but maybe that's just because i am not an electrician of any sort. Anyways electrician geniuses here's one to test you all out.
--Thanks in advance
12-23-08, 09:30 AM
#3
Firstly, I see this over and over and over....people working on the FD that don't have any business doing so. I say this by judging your moves made from your post. Fuel in the engine bay...Moving live wires around...ground out the battery = receipt for disaster. You are lucky you did not burn her down. One piece of advice - if you have the slightest inkling that you cannot safely achieve a repair, then don't do it.
Now, after that vent - what did your Shop manual tell you to check when looking at page Z-24 ? Oh wait, did you say you don't have a shop manual !!! Another vent - do not attempt to work on these cars without a shop manual and at the very least a grade 1 entrance level of auto mechanics.
This is not just aimed at you, poor soul...but everyone out there fiddling with an FD and trying to repair it yourself. Most times things get broken and the $$ figure goes ways UP.
If you think you know what you are doing, then go to page Z-24 of the shop manual and test all those front line fuses and see if any are blown.
Tell me you have a shop manual on the fender...
Later
Now, after that vent - what did your Shop manual tell you to check when looking at page Z-24 ? Oh wait, did you say you don't have a shop manual !!! Another vent - do not attempt to work on these cars without a shop manual and at the very least a grade 1 entrance level of auto mechanics.
This is not just aimed at you, poor soul...but everyone out there fiddling with an FD and trying to repair it yourself. Most times things get broken and the $$ figure goes ways UP.
If you think you know what you are doing, then go to page Z-24 of the shop manual and test all those front line fuses and see if any are blown.
Tell me you have a shop manual on the fender...
Later
12-23-08, 02:20 PM
#4
Thanks for the contributing post badddrx7. In answer to your questions, i would think i have some business working on the fd. You'll notice in the six line down i referred to the shop manual test, which i was following by having the live wire to get the fuel pump going. I am also not an idiot i took off my rats nest etc and cleaned up the fuel first thing so now i'm no waving around hot wires with an open pool of fuel on the LIM gap.
I am looking at my shop manual right now (yes my shopmanual i have) on z-24 and i am gonna dig further into this. Thanks at least for that tip on the page number. Nothing personal badddrx7, guys out there shouldn't be working on the car who screw things up without research, But the thing is that's not me. You were wrong on that one. I really was doing everything i should on this one, until i made a mistake, which sucks and happens to the best of mechanics every once in a while. And in case you're still questioning whether i know what i am doing with these cars or not, right now i am running on my engine that i rebuilt and streetported myself, nothing amazingly hard with a rotary but not something an idiot who doesn't own a shop manual can do
I have checked all the obvious fuses and they're good, and now i'll go take a look at a couple that z-24 brought to my attention. Anyone else have anything to contribute in helping solve this problem?
I am looking at my shop manual right now (yes my shopmanual i have) on z-24 and i am gonna dig further into this. Thanks at least for that tip on the page number. Nothing personal badddrx7, guys out there shouldn't be working on the car who screw things up without research, But the thing is that's not me. You were wrong on that one. I really was doing everything i should on this one, until i made a mistake, which sucks and happens to the best of mechanics every once in a while. And in case you're still questioning whether i know what i am doing with these cars or not, right now i am running on my engine that i rebuilt and streetported myself, nothing amazingly hard with a rotary but not something an idiot who doesn't own a shop manual can do
I have checked all the obvious fuses and they're good, and now i'll go take a look at a couple that z-24 brought to my attention. Anyone else have anything to contribute in helping solve this problem?
12-23-08, 04:16 PM
#5
Ok then, some credible kudos to you. I visited some of your other posts and a flag was raised. Now we'll see how good you are.
Pull the "big three" fuses....EGI, B2 and 120a main. Test them for continuity and re-install. Pull B1 - test and re-install. Also refer to page Z-20 for a layout of the electrical system.
One other thing, exactly what wire grounded out on the battery ?
Report back
Later
Pull the "big three" fuses....EGI, B2 and 120a main. Test them for continuity and re-install. Pull B1 - test and re-install. Also refer to page Z-20 for a layout of the electrical system.
One other thing, exactly what wire grounded out on the battery ?
Report back
Later
Last edited by badddrx7; 12-23-08 at 04:21 PM.
12-23-08, 05:43 PM
#6
*update*
don't flame me on this one lol but searching around and one of the engine harness ground wires was tucked away and hiding (from taking out rats' nest) and not grounding. Bolted it up to the engine for the time being and now my cluster is reading out, fuel guage is still off but mile display is back on. My stock ecu is now holding codes also so i am assuming that problem is relieved for the time being. Still am not gonna hook up the pfc l though until all this is through. Anyways now that that is working somewhat, but still a problem remains.
I am trying to get my fuel pump to prime the system so i can get pressure in there and see where it's leaking. Anyways hooked up hot wire to diagnostics pin f/p and GND up, and relay is clicking over also so no problem there. (that is what grounded out by the way GND wire on the diagnostic connector brushed positive terminal) Time to start checking for continuity at fuel pump related connectors etc right?. Pretty much done for the night i think so i'll get back on these tests tommorrowand let you all know.
oh and one little thing, when key is on the on position radiator fans are turning on by themselves and running. All heater controls etc are turned off. I found this somewhat odd. I'll start looking around in the diagrams i guess and see if fuel pump and fan wiring/fuses are connected somehow and if one shorting out might lead to the other not working....
don't flame me on this one lol but searching around and one of the engine harness ground wires was tucked away and hiding (from taking out rats' nest) and not grounding. Bolted it up to the engine for the time being and now my cluster is reading out, fuel guage is still off but mile display is back on. My stock ecu is now holding codes also so i am assuming that problem is relieved for the time being. Still am not gonna hook up the pfc l though until all this is through. Anyways now that that is working somewhat, but still a problem remains.
I am trying to get my fuel pump to prime the system so i can get pressure in there and see where it's leaking. Anyways hooked up hot wire to diagnostics pin f/p and GND up, and relay is clicking over also so no problem there. (that is what grounded out by the way GND wire on the diagnostic connector brushed positive terminal) Time to start checking for continuity at fuel pump related connectors etc right?. Pretty much done for the night i think so i'll get back on these tests tommorrowand let you all know.
oh and one little thing, when key is on the on position radiator fans are turning on by themselves and running. All heater controls etc are turned off. I found this somewhat odd. I'll start looking around in the diagrams i guess and see if fuel pump and fan wiring/fuses are connected somehow and if one shorting out might lead to the other not working....
12-23-08, 06:14 PM
#7
If it was the ground wire from the Diagnistic box that touched the battery, then you may be ok in that reagrd ( blown fuses, fried ECU, etc ).
Fuel Pump - Check for 12v at the FP relay Blue/Red wire and White/Red with the Jumper in at the DB. Maybe your Relay is rusty and not making contact. Yu can also check for 12 volts at the resistor ( below the master cylinder area ). The W/R wire is the one you want.
Later
Fuel Pump - Check for 12v at the FP relay Blue/Red wire and White/Red with the Jumper in at the DB. Maybe your Relay is rusty and not making contact. Yu can also check for 12 volts at the resistor ( below the master cylinder area ). The W/R wire is the one you want.
Later
Last edited by badddrx7; 12-23-08 at 06:19 PM.
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12-24-08, 07:14 PM
#9
ok here's what i've discovered so far
1.fuses-40ab2,120main, 60abtn,40b1,10aroom, all have continuity.
irregularites and problems fuse 15a air conditioning doesn't flow very much voltage at all (needle barely moves), BUT when fuse 40a B1 is pulled out air conditioning fuse sees 9 volts. weird.....
2nd problem- my fuel pump fuse is not seeing any volts (probably why my fuel
pump isn't working.... But here is what i am trying to figure out.... why it would do that. I'l give a quick rundown of other stuff real quick
Fuel pump, circuit opening, and EGI main all checked out good on resistance and conitnuity... However air pump relay not so hot Relay is good but no continuity on the terminals. My air pump is removed and wires cut would this change if i grounded those air pump connector wires?
Ok just went out and checked it again and this is weird. So you ground ou the two terminals and measure for voltage on the other rwo. Well when i did this i was getting a spark wheni grounded it out, and it would either click off (or on) my fuel pump relay. I thought this was kind of weird.. also after a second i saw some small amount of smoke ?! and now no reaction when i do that. maybe a fuse went out
so here is what i am thinking looking at page z-28 in the manual. if my 15a engine fuse has continuity, and all the relays i nthe engine bay and fuses alike have continuity, then maybe there is a bad wire/short between the ignition switch and the fuel pump fuse, or between the engine and fuel pump fuses. or a wire after it possibly connected to resistor. so my next step is to test continuity between the fuel pump fuse and the fuel pump connector (which isn't getting any voltage BTW. Maybe i can just put the wire to the positive terminal and then to the fuel pump and se if it operates. Then i might narrow it down to the resistor or one of the wires involved. Still a little confused about the air conditioning fuse getting voltage after other fuse removal and ari pump realy messing with my fuel pump relay. Anyone agree with my diagnosis up to this point? I'll get back after trying a couple of things. any suggestions on what else?
1.fuses-40ab2,120main, 60abtn,40b1,10aroom, all have continuity.
irregularites and problems fuse 15a air conditioning doesn't flow very much voltage at all (needle barely moves), BUT when fuse 40a B1 is pulled out air conditioning fuse sees 9 volts. weird.....
2nd problem- my fuel pump fuse is not seeing any volts (probably why my fuel
pump isn't working.... But here is what i am trying to figure out.... why it would do that. I'l give a quick rundown of other stuff real quick
Fuel pump, circuit opening, and EGI main all checked out good on resistance and conitnuity... However air pump relay not so hot Relay is good but no continuity on the terminals. My air pump is removed and wires cut would this change if i grounded those air pump connector wires?
Ok just went out and checked it again and this is weird. So you ground ou the two terminals and measure for voltage on the other rwo. Well when i did this i was getting a spark wheni grounded it out, and it would either click off (or on) my fuel pump relay. I thought this was kind of weird.. also after a second i saw some small amount of smoke ?! and now no reaction when i do that. maybe a fuse went out
so here is what i am thinking looking at page z-28 in the manual. if my 15a engine fuse has continuity, and all the relays i nthe engine bay and fuses alike have continuity, then maybe there is a bad wire/short between the ignition switch and the fuel pump fuse, or between the engine and fuel pump fuses. or a wire after it possibly connected to resistor. so my next step is to test continuity between the fuel pump fuse and the fuel pump connector (which isn't getting any voltage BTW. Maybe i can just put the wire to the positive terminal and then to the fuel pump and se if it operates. Then i might narrow it down to the resistor or one of the wires involved. Still a little confused about the air conditioning fuse getting voltage after other fuse removal and ari pump realy messing with my fuel pump relay. Anyone agree with my diagnosis up to this point? I'll get back after trying a couple of things. any suggestions on what else?
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