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Hi, welcome to jA.
Hi, thanks for the detailed information. Does sound like a tough one. I'm going to gather some wiring schematics and look this over and get back with you. I need to know if you'll have access to a voltmeter, for testing and I'll give some instructions. You'll have to bear with me as some testing may be repetitious for you, but i'll need to know the measurements in the order I give them so that we can issolate the fault. Let me know about acess to a meter and we'll go from there. Thanks,
I'm sorry, I haven't had a chance to post instructions...i've pulled up the wiring schematic, but haven't researched it yet, I should have a starting point for you shortly. Thanks,
Alright, the first step I need you to take is verify there is power going to the #1 fuse in the underdash fuse box. The fuse is rated 15 amps. It probably the one that's blown before. Use a voltmeter, and measure at both terminals of the fuse, with the fuse installed. I need to know exactly what voltage you read if any.
To begin, you'll need to change the fuse out with a 15 amp. Anything higher will either cause an electrical fire on this circuit, or wires to melt. Now, are you reading in DC volts scale on your meter? The voltage readings should not exceed 14.3 v max, if your reading 18.04, with the engine running - there is an overcharging issue. Let me know if this is corecct, becuase than we have few problems. The power supply failure to the dash, the engine not running, and the alternator is overcharging.
I'm sorry for not replying, infact I thought I had left a reply. With Superbowl weekend and all, it's been difficult to get to the information and back. If your not in too much of a rush, i'd like to continue this Monday, my original thoughts were you would not have voltage to this fuse, which would lead me further back into the circuit, but now i'll need to search upwards into the dash. Plus, I believe we may have a few concerns, becuase this fuse powers the cluster and the radio circuits, but shouldn't affect it running. Anyhow, if you don't mind it will be a few, otherwise your welcome to relist it under "prefer different opinion" and the question will open up to other experts who may be able to help sooner. Thanks,
No, definitly not...i'd like to help you get to the bottom of this. In fact, honestly, most of the techs frown on this type of problem because they know it can become very involved, but I believe i've tackled tougher ones 'online,' i'm planning to stop by the shop if I can later tonight - so if I do, i'll leave you a reply sooner. Thanks for understanding.
Alright, can you check for good voltage accross fuse #4 in the fuse box. This is the Siwtched Power fuse for the Cluster. I want to verify all power to the Cluster, before working at the underhood fuse box, where you found the wiring concern. If we find a fuse not supplying power, we can backtrack to the underhood fuses and wiring, and locate the source of our trouble. Thanks,
Great...now we have a starting point. I need you to access the Ignition Switch connector, and with the key ON, meaure for good voltage at the Black/Pink wire. Do this by keeping the connector connected and 'backprobing' the terminal in the connector for the Black/Pink Wire. Let me know the outcome, this wire supplies power to fuse #4. If it has no power, we need to check for good power going into the Ignition Switch. In fact, probe all the terminals of the Ignition Switch and tell me which ones have power (if any). Thanks,
Okay, done. I will specify the wires by the color of the wire first, and the stripe on the wire second. If I list the same color twice it is becasue there are two of the same color in the switch connector.
All were checked with the key on, door open, engine off, electric fan that is set to the key on position running, power antenna up (goes up with radio on or off). Battery is at 11.38 with the key off, 10.25 with it on and dropping. (I have it on a battery charger now).
We've found one problem. I know you've stated you've repalced the Ignition Switch, but somehow I think it burned out. The Black/Pink wire should have voltage as well with the key on, it powers part of the Cluster, and the Ignition Coils. So, I still not sure what is going on under the hood fuse box, but have it set to where the enigne was running before, and I'd like you to use a long wire (10 guage) and connect it to the battery positive, bare some of the Black/Pink wire and connect this "jumper wire" to it. See if the Cluster comes on and the engine runs...your doing a good job! Let me know the outcome. Thanks,
Your right, I overlooked 1 wire - sorry. I notice you don't have power on the Yellow/Black, this is for the starter relay. But I also noticed you measured no voltage on the Blue/Orange. This is what i'd like you to do. Cut the Blue orage wire at the ignition switch connector, for testing purposes. Make sure you leave about 2" at least so we can reconnect it with a crimp when were ready. I'd like you to connect your jumper to the end going into the ignition switch, and see if everything works than. The reason I want you to cut it, is that if the other end is shorted somewhere under the hood, it can cause problems, so this way were issolating it from the circuit. Let me know what happens.
I was able to pull the blue/orange wire terminal out of the plug. It is really tight under this dash and I did not want to have to solder and heatshrink up in there later. I don't really like crimp connectors either, this way I can just insert the terminal back in place when we get this figured out.
I put my jumper directly to the ignition switch in that blue/orange wire position and the car started up when I actuated the ignition key as normal. Also the cluster lit up and worked. Just to see what would happen I pulled the jumper out and the car stayed running, but the cluster went blank. It would not restart with the jumper removed as well.
So now you have led me in the right direction. The car will run and the cluster will work when jumped. The car will stay running, but I loose the cluster if I disconnect the jumper.
Good Job! Now, the Blue/Orange wire is supposed to get power from the underhood Start Interrupt Relay, and this relay gets power from fuse P in the underhood fuse box. So first, reinstall the terminal into the switch connector. Go to the fuse box under the hood and measure the voltage on the fuse for P . Let me know if fuse P has good power on both sides.
If fuse P has good power, i'll need you to locate the Start Interupt Relay under the hood. It has (4) wires going into the connector [Light Green/Purple, Yellow Black, Dark Blue/Orange, and Yellow.] Let me know if you can locate this relay so we can make some further tests and come to a conclusion. If you can't locate it, i'll find and eact spot tommorow morning, and can post it here. Let me know your findings. Thanks,
Alright, give me until tommorow morning...my schematic shows it going under the hood, but there's a chance it's under the dash. I'll find the location and let you know. Thanks,
Alright, the starter inturupt relay is actually under the right side of the dash, next to the Airbag Diagnostic module. It's doesn't say in my information how exactly to access it, but from my experience you usually have to remove the glovebox and the dash undercover. We need to make the tests at the relay there are only three possibilities left - the relay is bad, the wiring power supply to the relay is broken, or the Anti-theft module is not sending a signal to turn the relay on. Let me know if you still have difficulty locating it.
I found it. While trying to engage the starter with the ignition switch I get:
Green/Purple 8.36 (battery is getting low)
Sorry for the delay. i'm researching and i'll be with youin a minute.
Bill, I think we've found our problem. A possible broken wire from fuse P to the relay. The Yellow wire on the relay should have battery voltage. Could you double check and make sure it does? If no voltage, see if you can do the same here and remove the wire from the connector and use your manufactured jumper wire to add power to this Yellow wire - see if the engine runs and everything works properly.
Okay, we seem to be in the right area.
I rechecked and it had 12+ volts at the yellow wire, back of the relay (battery charger is hooked up).
I tried to start the car, it started and ran, but the cluster did not come on.
I shut the car off, tried to restart again, and nothing.
Current conditions: 12+ volts at yellow wire at relay with key in off position.
Turn key to run and voltage drops to 0.22.
Try to start and voltage reads -0.03.
Put key back to off and 12+ volts.
Cluster still does not power in any positon.
I was not sure if I should run the jumper under these conditions and wanted to report to you first.
I'm not sure if you already did, but can you measure the voltage accross fuse P, with the ignition On? I want to know if it also goes away. Thanks,
Okay, I've checked this morning and now there was no power to the yellow wire at the relay in any position of the ignition switch.
I checked the voltage across fuse P and it is good in off and run position, so it is not going away there.
Than I wanted to run one more test and I got my son to help.
I wanted to check to see if the what happened to the power at fuse P when the starter was activated by the ignition switch.
While testing fuse P with the key in the on position, my son told me that the cluster turned on. I had him turn the key and the car started.
I disconnected the test leads and started and shut of the car two times with success.
Current conditons are: The car operates normally. Cluster comes on, and car starts and runs with no jumpers or test leads in place.
Bill, there's a problem with the wire from fuse P to the relay. The problem seems to be under the fuse block, it seems when you disturb it is when it operates. Take a look underneath and see what you find.
I looked undernearth and everything looks okay, the problem may be concealed. How do I check for this?
Is there any possibility that the anti theft system is causing this now intermittent problem?
I dont believe the anti-theft is causing the problem, if there is no voltage on the Yellow wire, it has to be from the fuse to the relay. If the anti-theft was causing the concern you would have no ground on the Green/Purple wire to the relay (this is the anti-theft module ground signal). So either there is a break in the Yellow wire to the relay or a bad connection somewhere. It's becomes difficult from here to test for a broken wire. You'll need to disconnect the wire at both ends (relay and fuse) than place your meter leads on each end, and cehck for good continuity, while wiggling the wiring thru the harness. If the continuity becomes "open" during the testing you can further issolate this concern. In most cases if the break is somewhere deep in the harness, we'll need to retrofit an aftermarket repair, by placing a new "known good" wire along the harness. So this may end up being your option. If you run the jumper from the fuse to the relay and the engine and cluster operate without interuption, the best remedy would be to place the jumper permenantly (solder) into the circuit, and disconnecting the Yellow wire completely.
Yes it does, but technically not straight - it winds along the harness bends and enters the dash thru the firewall. You should be able to follow it in the harness, by opening the harness at different intervals.
I found the problem to be the connection of the 25 amp fuse at the p position. That is why when probing the top of the fuse the power would come on and off. Now I have a good constant power to the relay inside the car. I tightened the terminals a bit and put a new fuse iin that position. However, the cluster is now powering on intermittently. At first I had the cluster working fine, but after cycling the key several times it went dead. I was able to see it power up one or two times, but now it is completely inactive. I can start the car, but the cluster remains completely blank.
I have the day off today, so I went back over our initial checks and found no further problems. I poked around in both the under dash fuse box and the power supply. I checked connections at the ignition switch and everything seemed okay.
So I cycled the key again and the cluster came on and everthing was working fine.
I than remebered that the previous owner of this car had complained about leaving the car at a repair shop one time and the car being parked in an area that flooded. He had told me that the car had been partially submerged, but the shop had cleaned the car up and detailed it fully.
My theory is that I am experiencing problems due to corrosion on some of the terminals. Some making contact just enough to operate some systems, but occasionally loosing their contection due to humidity, tempurature, etc.
So, I have now cleaned all of the connections in both fuse blocks, the ignition switch, and the starter inturrept relay. I sprayed them with an electically contact preservent I use on my boat and swamp buggy. I than put dilectric grease on every contact point.
I re-installed everything and all works perfectly.
I thank you for your help and will request you personally if possible next time I have a problem.
Good job on the testing, and thanks for the accept. This was a difficult problem to locate but you stuck thru it and got it done...i'd enjoy helping you in the future if you will need it. Thanks,