Taurus Car Club of America : Ford Taurus Forum banner

1 - 20 of 85 Posts

·
Registered
Joined
·
955 Posts
Discussion Starter · #1 ·
Within the last two days an interesting scenerio has been happeing... but at completely random.

It started while I was at a stop light. I wasn't really paying attention but I felt the car kinda of jerk like I had been bumped from behind (and that's what I thought it was b/c the truck was really close to me in the rear-view). When I let off on the brake the car didn't go anywhere and that's when I noticed all the dash lights on (idiot lights as some call them) and the RPM's at 0.. the car had just stalled!

I put it in Park and started again with no problems for the rest of the night.

Now lastnight, I go out and start the car after going to dinner with some friends. Within only 5 mins of bs'ing with the friends the car was idling and stalled (same problem with all the lights on again and no RPM's). I restarted and it happened one more time a few minutes later.

I started driving after it stopped misbehaving and the THEFT light came on in which I felt the car jerk a bit (small like dropping from Odrive to Drive) and then the Theft light went out and it drove like normal. The theft light came on once more.

All and all this was only 10-15 mins after starting the car. After that no symptoms occured for the rest of the trip home (about another 15 mins or so).

Any ideas? I see that a bad battery or alternator could be causing some of this. The only thing is that I just had the battery replaced about 3 months ago and I believe that it is working just fine. I have noticed that the Serpentine Belt system is still squeeling (even after replacing the idler pully - have a write up in the Common Problems section). The squeeling is pretty high on the pulley system, right around the Alternator. Could my alternator be gonig? If so, what are the symtoms and is there some way to check?

Thanks in advance. I hope I have provided enough information and a clear enough description to get some good responses!

~Ricer333

01 SES
115K miles
3.0 Vulcan
 

·
Registered
Joined
·
2,471 Posts
Within the last two days an interesting scenerio has been happeing... but at completely random.

It started while I was at a stop light. I wasn't really paying attention but I felt the car kinda of jerk like I had been bumped from behind (and that's what I thought it was b/c the truck was really close to me in the rear-view). When I let off on the brake the car didn't go anywhere and that's when I noticed all the dash lights on (idiot lights as some call them) and the RPM's at 0.. the car had just stalled!

I put it in Park and started again with no problems for the rest of the night.

Now lastnight, I go out and start the car after going to dinner with some friends. Within only 5 mins of bs'ing with the friends the car was idling and stalled (same problem with all the lights on again and no RPM's). I restarted and it happened one more time a few minutes later.

I started driving after it stopped misbehaving and the THEFT light came on in which I felt the car jerk a bit (small like dropping from Odrive to Drive) and then the Theft light went out and it drove like normal. The theft light came on once more.

All and all this was only 10-15 mins after starting the car. After that no symptoms occured for the rest of the trip home (about another 15 mins or so).

Any ideas? I see that a bad battery or alternator could be causing some of this. The only thing is that I just had the battery replaced about 3 months ago and I believe that it is working just fine. I have noticed that the Serpentine Belt system is still squeeling (even after replacing the idler pully - have a write up in the Common Problems section). The squeeling is pretty high on the pulley system, right around the Alternator. Could my alternator be gonig? If so, what are the symtoms and is there some way to check?

Thanks in advance. I hope I have provided enough information and a clear enough description to get some good responses!

~Ricer333

01 SES
115K miles
3.0 Vulcan
[/b]
Why not consider running this puppy by your favorite autoparts store, for a no cost, in vehicle, electrical system check-up, via their portable electrical system tester.

It can properly load test the entire electrical system, with everything in place, in the vehicle.

Propoerly used, it can sniff out problems like, faulty, or leaking alternator diodes, loose battery cables or ground straps, or dirty/corroded electrcal connections, including excessive battery cable voltage drop, weak, or shorted battery cells & even slipping belts!!!!!

Let us know what you find.
 

·
Premium Member
Joined
·
1,318 Posts
Try putting it in drive instead of overdrive. It almost sounds like the Torque converter clutch is engaging when it isn't supposed to, but I don't know what the actual symptoms of that happening are. I just know that if the TCC was to engage when it wasn't supposed to, it would instantly stall the car. All the idiot lights going on would be the car going back into bulb check mode because the engine shut off. That's my best guess anyways.

I don't know why the theft light would go on and off though.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #4 ·
<div class='quotemain'>
Within the last two days an interesting scenerio has been happeing... but at completely random.

It started while I was at a stop light. I wasn't really paying attention but I felt the car kinda of jerk like I had been bumped from behind (and that's what I thought it was b/c the truck was really close to me in the rear-view). When I let off on the brake the car didn't go anywhere and that's when I noticed all the dash lights on (idiot lights as some call them) and the RPM's at 0.. the car had just stalled!

I put it in Park and started again with no problems for the rest of the night.

Now lastnight, I go out and start the car after going to dinner with some friends. Within only 5 mins of bs'ing with the friends the car was idling and stalled (same problem with all the lights on again and no RPM's). I restarted and it happened one more time a few minutes later.

I started driving after it stopped misbehaving and the THEFT light came on in which I felt the car jerk a bit (small like dropping from Odrive to Drive) and then the Theft light went out and it drove like normal. The theft light came on once more.

All and all this was only 10-15 mins after starting the car. After that no symptoms occured for the rest of the trip home (about another 15 mins or so).

Any ideas? I see that a bad battery or alternator could be causing some of this. The only thing is that I just had the battery replaced about 3 months ago and I believe that it is working just fine. I have noticed that the Serpentine Belt system is still squeeling (even after replacing the idler pully - have a write up in the Common Problems section). The squeeling is pretty high on the pulley system, right around the Alternator. Could my alternator be gonig? If so, what are the symtoms and is there some way to check?

Thanks in advance. I hope I have provided enough information and a clear enough description to get some good responses!

~Ricer333

01 SES
115K miles
3.0 Vulcan
[/b]
Why not consider running this puppy by your favorite autoparts store, for a no cost, in vehicle, electrical system check-up, via their portable electrical system tester.

It can properly load test the entire electrical system, with everything in place, in the vehicle.

Propoerly used, it can sniff out problems like, faulty, or leaking alternator diodes, loose battery cables or ground straps, or dirty/corroded electrcal connections, including excessive battery cable voltage drop, weak, or shorted battery cells & even slipping belts!!!!!

Let us know what you find.
[/b][/quote]

Well I just had a battery and electrical system load check (done on the Alternator). The results came back as a bad diaode (spelling?) in the alternator. So once again TCCA members are right on! The options I have at this AutoZone were for two Duralast Alternators.

(1) Duralast Gold rated at 110 Amps ~$200
(2) Duralast reman rated at 130 Amps ~$170

Both carry the same warrenty. My question (because I'm not an electrical guy) is what is the difference in the Amps? What does 20 more amps buy me and is it possible to have TOO much power (Tim the Tool Man Taylor would not agree).

I'm going to buy a new gator back belt too to replace my current seeing as I have to remove the belt anyways.

Thanks in advance. Hope I hear something from members soon so that I can do this today!

~Ricer333
 

·
Registered
Joined
·
2,471 Posts
Having a heavier duty alternator (higher amp output rating) won't hurt your electrical system.

If you have lots of extra electical load items on the vehicle, or think you may be adding more in the future, the extra amp load capacity wouldn't hurt.

Good idea on the new "Gatorback" belt. I hear nothing but positive things about it.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #6 ·
well it's done.
I chose to go with the remanufactured Duralast 130 amp Alternator from AZ. I also got a new Gatorback belt and put that on.

The only trouble through the entire thing was getting the old belt off (didn't want to cut it so that I could keep it in the trunk just in case). The damn clutch for the AC just didn't want to cooperate. But the patience persisted and I got it off.

Took about 1hr from start to finish. Took it back to AZ returned the core and had them run the load test again.... All Passed! A+

Thanks guys I feel like I actually did something on my Sunday :mj_banana:
 

·
Registered
Joined
·
2,471 Posts
Good to hear you got it all put right & are "on the road aagin"!!!

Good idea to have them load test the new alternator in the system.
Good idea to save the old belt too. I have a couple of old bets in my Taurus & Ranger too, just in case!!!!
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #8 ·
So,
The theft light issue just popped up again. I ran it down to AZ and the guy tested the battery and load tested the alternator. While I was at ~2000 rpms the voltage was something around 13.4-13.6 (i think it was voltage it was the top number of the two on the machine). He said everything looked good.

Any other ideas other than the Torque Converter? Could something have been damaged in the GEM (I think that's what controls the theft system) and is there a way to test for that? Or could something be going on between the car key and the theft transceiver (not sure how exactly the theft system works).

Any ideas would be great. The only thing added was the Radar detector (located in another post) but I think everything is working fine there.

Thanks. BTW, this happened 2x today and hasn't happened since the alternator was replaced.

~Ricer333
 

·
Premium Member
Joined
·
14,126 Posts
Classic symptoms of low voltage at the battery. What is happening is the battery saver relay is dropping out due to low voltage. This cuts out the PCM too.
When the relay turns this stuff off the voltage will then raise due to the way a battery works. Then the the PCM reboots. This is when the all the warning lights flash on and off. Then the voltage drops and the battery saver kicks in again. This just keeps happening until the battery cannot recover.

A new battery and alternator at 2000 rpm should be putting out 14.4V even with a minor electrical load.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #10 ·
Well,
I started seeing the problems once again. This makes it what, 3 weeks this time? I was driving down the highway Monday night when I noticed my Passport Radar on the Voltage setting displaying voltages ALL over the place (11.0-14.1). When it would drop too low, a LOW VOLT would appear. Right around the same time, I would notice my headlights flickering and at times the THEFT light appearing (see above for the entire theft light issue).

I kept my eye on it and Tuesday and the theft light killed the car in my apartment complex. When the power came back on (i turned the car over) the radio was all STATIC! All the presets were there but I couldn't get anything to tune in. The CD player would work if the voltages on the Radar display weren't jumping around. IF they were jumping around the CD player wouldn't work (showed TRACK 0).

So, I took it to a newer mechanic. One that had come recommended (mainly b/c the labor chargers were lower than I was used to). I explained the previous happenings and the fact that I was on my 2nd reman AZ alternator.

The mechanic (rather another guy working for him) tested the hell out of the Alternator and Battery and everything in between. He could not see any 'adnormal' drops in voltage. The radio was turned off when I delivered the car, but I did explain to the main mechanic the radio problem. However, the mechanic that was working on it never got that knowledge. When I talked to him later Wednesday, I informed him of all the history and work that I had done.

I informed him that my gut said that the radio static was involved. I had a feeling that the radio static was involved b/c when it happened, I never saw the voltages dip again! From the trip to work to the mechanic, and of course the mechanic never saw anything even with load testing the hell out of it.

So he pulled the schematics and traced it to either the ICP (interior control panel) or the RCU (Rear Control Unit). Now TCCA, this is where I want you to veryify for me what the mechanic said.

He tested all the leads coming and going from the ICP and found nothing at fault. He disconnected the RCU and truly believes that this is the source of the static and the source of the shorting out, which would have cause the theft light issue along with making the alternators work too hard and thus shortening their lives.

He has had it disconnected and I currently have it disconnected. So I ask you, does this seem right? The radio will not work b/c he said that the RCU feeds power to the ICP. Is this true? I thought that the ICP was hooked directly to the battery as well, so why would the RCU control whether the ICP gets power or not?

Could this have been the issue all along? Would the RCU shorting out give me static? If so, I want to replace this part, which doesn't look all that hard to do. I have been carefully eyeing the Radar Volts. If I remove this part, is there a way to test it to see that it shorted out? (visual burn or some other method)?

Please weigh in with your knowledge. The mechanic made it sound like the battery is connected to the RCU and the ICP, but the RCU and ICP and battery make a circuit and if the RCU was shorting it could produce the dip in volts thus triggering the Theft light issues and acting like an Alternator issue.

Thanks again and I look forward to your knowledge.
~Matt
 

·
Premium Member
Joined
·
14,126 Posts
Sounds like you are treading on new ground. I guess we shall see if it fixes it or not eh?
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #12 ·
yeah this is new ground!

as i said above, the rear control unit is unplugged. i looked at the schmatic in the Haynes manual and I do see how it connects to ICP and the speakers.

So here is the $140 question, where the heck can I find a good RCU? Anyone on here know? Also, are RCU's for all gen4's equivalent? So if I find a 96-01 Taurus/Sable I can just rip it out and put it in mine?

Thanks all!
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #13 ·
Anyone know what the part number is on the Taurus RCU? :dunno:

I am having one heck of a time searching for this part. I can't seem to find it under RockAuto. If anyone knows the part number or any other good sites, please post back.
 

·
Premium Member
Joined
·
14,126 Posts
You will have to get this at an OEM parts dealer or at a JY. No aftermarket stuff for this.

I'd be driving around for a week or so with the RCU disconnected to be sure that's the problem.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #16 ·
01 Part# - YF1F-18C851-AA.

I had disconnected this part and drove around for about 2-3 days. No issues! Went to a junk yard and pulled the same number from an 01 SE. Plugged in and tested and it worked.

The JY wanted $42.50 for it, which was good because some wanted $85-100 for the same part. Btw, most JY call this a Signal Processor, not a Rear Control Unit.

Been driving around with this unit installed since Saturday (so like 2 days) and so far no issues. The voltages are jumping around a bit (13.1-14.1, with the occasional 12.9) but nothing like it was just before the speakers went static.

I sincerely hope that this was the issue. That back in December when the original Alternator went that it damage this RCU/SP in such a way that it was shorting and drawing the cars voltages down enough to reset the PATS module.

Thanks TCCA and hopefully this can officially be done with! :x:

And a special shout-out to SHOZ123 with the help via PM's! Thanks again.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #17 ·
well, it's BAAACCKK!! :angryfire:

I ended up replaced the RCU (as stated above) thinking that it had shorted out and was intermitantly grounding out, putting stress on the Alternator and causing the car to shut off.

well, yesterday morning I come out to a dewy car, start er up, and start down to work. Half way there (4-5mins driving) the radar detector voltages are all over (jumping from 11.0 - LOW VOLT up to 13.8 in a matter of milliseconds)!!

I take it down to the mechanics that were testing it before and told me the RCU should fix the problem and they can't find anything wrong... needless to say it didn't do it. I had foolishly shut the car off to go in and talk to them, when I started it back up NOTHING!

So I start going back to work and have to pull in for some gas. It starts acting up AGAIN! So I wheel around and take it to my old mechanic, call them up and tell them I need them to see something right away. I'm 2 friggin' stop lights away (in which I catch both Red lights) and at the second one the car stalls out (literally 300 yrds from the shop). I put it into Park, start er up and all is FINE :dunno:

Of course for the 15 mins that the car is parked and running at the shop nothing out of spec happens.

The mechanic said that it could be a control module (computer) that is damaged. He said that one of the modules (GEM?PCM?) 'tells the alternator when to charge and when not the charge. IS this true? I thought the alternator was always charging.
I think I may have pissed him off a bit b/c from the knowledge that I have learned here I gather that those control modules are the last things to go (rather bullet proof). Well he starts in saying "I'm certified, I've been in this business for 20yrs".

So anyways, I am not going to bring it back UNTIL it is constantly replicating the problem. But I want to ask TCCA if there are some grounds (engine to firewall, engine to chassis, others) that I can check and double check (how do I specifically check them btw?).

I can't keep tossing alternators, RCU's or whatever else at the problem. I do believe that the idiot lights coming on and rpm's dipping is due to a module rebooting b/c the voltage dropped too low (as SHOZ123 has explained).

Just looking right now for ways to test for loose wires/electrical ground outs. When you write back please be specific to where this stuff to test for is.

Thanks TCCA. I'm coming close to trading this in if this problem cannot be resolved cheaply and forever!

~Matt
 

·
Premium Member
Joined
·
14,126 Posts
Well there is no way the battery voltage is going up and down that fast. You have to have a bad wire or connection between the battery, either ground or the hot wire.

If you car is like my '97 then the POS wire has two leads. One to the starter and one to the MEGA fuse. The MEGA fuse wire is what feeds the entire car and the starter wire is only used when starting. If the power is going down to 0V when the engine is running then it would have to either both connections (alternator wire and battery wire) at the MEGA fuse, or the positive battery post at the battery or the battery ground.

The main battery ground goes from the neg. battery post to the starter. I think there is also a minor one that goes to the drivers side fender. But still if the voltage is dropping to 0V then it has to either be both of them or the connections at the battery.
 

·
Registered
Joined
·
2,471 Posts
Seeing as how the problem seems to have cleared up after you last replaced the alternator, pay close attention to the electrical connections at the alternator. If you don't find any suspects there, maybe try the following.

A fast easy way to check suspect connections or leads, without expensive test equiptment, is to parallel connect another known good lead, along the same path of the suspect.

A good set of low resistance, heavy gauge, jumper cables can be used to quiclky test the battery to engine, body & starter ground wires, or ground straps.

If the problem clears up, then remove one parallel ground at a time, until the problem returns, then that connection is the troublesme suspect.
Check that leads connections for corrosion, loose fastners, terminal crimps for crrosion, or looseness, or broken wire strands.

If bad grounds don't prove out, then parallel the B+ feed from the battery to the underhood power distribution box, with one of the jumper cables & see how that goes.
If the problem clears up, suspect the B+ lead, or it's connections.

Let us know what you find.
 

·
Registered
Joined
·
955 Posts
Discussion Starter · #20 ·
Well there is no way the battery voltage is going up and down that fast. You have to have a bad wire or connection between the battery, either ground or the hot wire.

If you car is like my '97 then the POS wire has two leads. One to the starter and one to the MEGA fuse. The MEGA fuse wire is what feeds the entire car and the starter wire is only used when starting. If the power is going down to 0V when the engine is running then it would have to either both connections (alternator wire and battery wire) at the MEGA fuse, or the positive battery post at the battery or the battery ground.

The main battery ground goes from the neg. battery post to the starter. I think there is also a minor one that goes to the drivers side fender. But still if the voltage is dropping to 0V then it has to either be both of them or the connections at the battery.
[/b]

Sho,
the voltage is not dropping down to 0v. It's jumping from 14.1v to 11.0v in a matter of milliseconds when the problem arises. It has not acted up yet, but when it does I will be testing everything I can (also trying to enlist the mechanic). This problem has to be something like a loose wire/bad wire that just happpens to break in the right circumstances. Btw, what about this whole Control Module (PCM?) issue. Could it be bad?

One thing that I have noticed when this issue happens is a smell (not too strong) in the cabin of the car. It smells like electrical heat.. you know? Could there be something shorting out in the dash or the column? If so how would I check?
~Matt
 
1 - 20 of 85 Posts
Top