Gus_Mahn
Well-Known LVC Member
i'd use a relay, and use your switch to switch the relay. I'd take the power off of the hot post on the alternator. There are adjustable thermal fan controllers if you want to automate the fan operation.
'03 LS8 Fan Failure
- Thread starter SoulSoak
- Start date
Yes I installed an inline fuse above driver side feet. And yes, I basically tapped into the wiring harness on the fan side and on the live side. I can still easily connect it back to factory.
And as to Joe's response, I feel the same. My fan functions, the PCM is simply failing to tell it to do so. Which likely means, the PCM could be failing to do several things, which isn't safe to be driving.
Now I also understand that this setup is far from the most economical in the long run, but with just minimal commuting I'm hoping it will hold up fine until tax returns. Me and my wife have been really struggling lately, and we can't juggle the Fusion.
I thought ahead when doing this, my amp remote wire runs directly under my fan switch. So as soon as I get this diagnosed and fixed, I'll simply wire the switch to control my amp.
Anyhow, thanks for all the advice and concern. I'm sure I'll be fine until it's properly fixed, I live by God. Granted, many are realists. I go by Faith.
God bless and good morning
joegr
Dedicated LVC Member
Why use a relay? He's switching the logic supply to the fan. It draws less than one amp of current.
oddball
Dedicated LVC Member
I strongly recommend you follow Joe's advice and try to see what the PCM knows about the engine. You can get a $10 bluetooth ODBII module and Torque on your phone. If the temp doesn't make sense, then there's an issue.
I **think** you can also measure the voltage of the white wire. That is absolutely not the correct way, but you don't have the equipment for that. You should get at least some reading there as the engine gets warm.
My guess is the white wire got broken somewhere. You can do a continuity test on that wire, but may also just need to follow it and make sure it isn't pinched or broken.
I **think** you can also measure the voltage of the white wire. That is absolutely not the correct way, but you don't have the equipment for that. You should get at least some reading there as the engine gets warm.
My guess is the white wire got broken somewhere. You can do a continuity test on that wire, but may also just need to follow it and make sure it isn't pinched or broken.
Thanks for the advice. Do you happen to know the route this PCM fan wire takes? I'll do some investigating when I get home from work.
lincolnelite
Well-Known LVC Member
I don't think it will be fine if you're stuck in a traffic during summer. I guess you drive your car occasionally and doesn't get stuck in traffic.
joegr
Dedicated LVC Member
It's not the fan wire that you need to follow. We know it's good. If it weren't, the fan would be full on all the time the key is on.
It's the temperature sensor wires that you need to follow.
Oh, I was under the impression that the other smaller wire (the one that isn't jumped) was faulty. I thought that it was a signal wire for the PCM and it wasn't working properly.
Hey Joe would you mind setting me on the path to these temp sensors?
joegr
Dedicated LVC Member
The fan is fail-safe. Once it gets power on the logic power line, the PCM has to constantly send it a PWM signal indicating what speed it wants. If the wire is broken or shorted to ground or power, the fan will run at full speed. You've verified that the fan works by jumpering logic power, so the only way it isn't running is that the PCM is telling it not too. Now you need to determine why the PCM is telling it not to run.
Well this didn't take long lol. I'm throwing in the towel.
NOT ON THE LS THOUGH!!! I don't care if I gotta sleep in the street next to it... No way will I let her go.
Anyhow, long story short. I went to do a few errands after I got out of work, maybe 10 miles tops. Came home. Once I got home, I realized I left my cell phone in my freezer coats pocket at work. So I get back in the car, the car temp needle JUST reached horizontal (up to temp) when I initially pulled into my driveway. Anyhow... off to work.
On my way to work, I'm cruising on the main road at approx. 50mph and my temp gauge starts to creep. I end up making a left turn onto the industrial road my work is located off of. The needle goes up to 3/4, then back down a little bit. I park the car and pop the hood. I get out and feel around the engine... The damn thing is still rather luke warm. NOT HOT!! I squeeze the radiator hoses, they are pressurized and are "warm".
I hop back in the car, turn the key to run to inspect gauges... and of course the needle is exactly horizontal. I start the car back up, drive about 75ft, and it goes up to 3/4 again. I stop on side of road, put it in park and shut the engine off. DIRECTLY after shutting the engine off, I turn the key back to run position and the needle is HORIZONTAL AGAIN...
I don't think that the temp could go from 3/4 then reset back to horizontal just by killing the engine and turning the key back to run. Something is electrically/sensor wise wrong. Because I recall before I did my cooling system overhaul in August, that when my car actually overheated my needle read 3/4... and the coolant was boiling and the engine was HOT.
So I guess it's safe to say, I have a faulty temperature sensor somewhere... or my PCM is taking a crap. My shifting is fine, the car responds great etc. I will note that there is a slight whistle coming from my intake... but that was present before.
Guess I'll connect the fan back to factory, and take the car to the dealer. Can't wait to hear the wonderful news from them. My wife is going to kill my ass.
I'll update after they run diagnostics, and I'll fill you guys in. Man... the love I have for this car, and the love I give it.... it sure hates my ass lol.
NOT ON THE LS THOUGH!!! I don't care if I gotta sleep in the street next to it... No way will I let her go.
Anyhow, long story short. I went to do a few errands after I got out of work, maybe 10 miles tops. Came home. Once I got home, I realized I left my cell phone in my freezer coats pocket at work. So I get back in the car, the car temp needle JUST reached horizontal (up to temp) when I initially pulled into my driveway. Anyhow... off to work.
On my way to work, I'm cruising on the main road at approx. 50mph and my temp gauge starts to creep. I end up making a left turn onto the industrial road my work is located off of. The needle goes up to 3/4, then back down a little bit. I park the car and pop the hood. I get out and feel around the engine... The damn thing is still rather luke warm. NOT HOT!! I squeeze the radiator hoses, they are pressurized and are "warm".
I hop back in the car, turn the key to run to inspect gauges... and of course the needle is exactly horizontal. I start the car back up, drive about 75ft, and it goes up to 3/4 again. I stop on side of road, put it in park and shut the engine off. DIRECTLY after shutting the engine off, I turn the key back to run position and the needle is HORIZONTAL AGAIN...
I don't think that the temp could go from 3/4 then reset back to horizontal just by killing the engine and turning the key back to run. Something is electrically/sensor wise wrong. Because I recall before I did my cooling system overhaul in August, that when my car actually overheated my needle read 3/4... and the coolant was boiling and the engine was HOT.
So I guess it's safe to say, I have a faulty temperature sensor somewhere... or my PCM is taking a crap. My shifting is fine, the car responds great etc. I will note that there is a slight whistle coming from my intake... but that was present before.
Guess I'll connect the fan back to factory, and take the car to the dealer. Can't wait to hear the wonderful news from them. My wife is going to kill my ass.
I'll update after they run diagnostics, and I'll fill you guys in. Man... the love I have for this car, and the love I give it.... it sure hates my ass lol.
Ford dealer should be just fine. I have a Ford dealer much, much closer than the Lincoln dealer and I've been there a few times.
scjmc
Dedicated LVC Member
I use my local Ford dealer. Hopefully 1 hour labor will tell you everything that you need to know. That's been my experience mostly.
oddball
Dedicated LVC Member
joegr
Dedicated LVC Member
I wonder if you might have pinched the head temperature sensor wire when you reinstalled the intake manifold? Let's hope it's as simple as that.
Indeed, I can only hope. Although, if that were the case... Should I just pay them for the diagnostic and take it home to pull the intake and replace the wire myself? I would imagine if they have to pull the intake, I'm going to be getting bent over hard $$$ wise.
They called today. Told me there was a wiring issue with the fan, and also told me that the radiator was clogged. Now personally if the radiator was clogged, I don't understand how I was able to drain it when I did my cooling system last August. But maybe they meant it was clogged from the outside behind the front bumper cover. I would think I would have noticed that though. Regardless, they're charging me $220 for everything. And I also decided to have them flush the trans while it's already at the shop. Gonna be $400 for everything altogether. Hopefully no more overheating. Will be picking it up today, but with this weather... I won't be able to drive it to find out. I'll update when I get the chance.
Got her home now. No overheating issues. I won't feel comfortable until I've got a good month without any hiccups though. Anyhow, the car feels like it received a brand new Trans, it shifts great and doesn't delay at all between reverse and drive etc. It used to kinda slam into reverse.
All in all, $320 later... As long as my overheating gauge/issue remains absent I'm happy. God bless fellas
All in all, $320 later... As long as my overheating gauge/issue remains absent I'm happy. God bless fellas
scjmc
Dedicated LVC Member
Well Mine arrived today. Perfect, brand new OEM 4 wire connector fan for $225. Amazon price is now $781.29.
Glad that you got yours straightened out SoulSoak.
Telco
Dedicated LVC Member
Crap will blow through the AC condenser, losing enough velocity to pack in around the radiator. The end result: a wall of crap between the condenser and radiator as tightly sealed as though you stuck a piece of Styrofoam between them. Where my mother lives, Tyson Foods regularly runs chicken trucks. Every two years or so her truck's radiator has to be removed and plucked because feathers will pack into that little section.
scjmc
Dedicated LVC Member
Sorry, I missed this post earlier. You are right that it would not be good stuck in traffic in the summer. I drive my LS daily, and I live in eternal summer. I simply haven't had time to replace the fan yet. I did get my new Motorcraft replacement yesterday though. I should be able to install it this weekend hopefully.
Luckily for SoulSoak his fan was OK.
Jeff M
LVC Member
OK, I'm bring this one back from the dead since my 03 LS V8 is having the exact same issue. Fan doesn't run at all but does have power and runs when it's jumped. I know SoulSoak's car was a wiring problem that the dealer wound up fixing but I'm looking for troubleshooting advice to start ruling out circuits and sensors. Trying to avoid the dealership of course. It's August and I'm in Florida so unless the car is moving it's going to overheat.