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Discussion Starter #1
On my '94 Fleetwood, this just started a couple days ago and I haven't quite nailed down what's happening, but based on observation I have a couple ideas/theories. I noticed while driving that my stereo would unexpectedly completely lose power, and then come back on and start playing again. FYI - aftermarket stereo, Pioneer touchscreen double DIN unit, been in since I bought the car 1½ years ago, no issues until now. At one point it finally lost power long enough to actually lose all saved settings and when it came back on it was back to all factory defaults. Normally I would just chalk it up to something is wrong with the stereo itself, or the wiring. Here's where it gets weird though, it only happens when I'm turning left. Not every time, but it was getting progressively worse and more often than not if I turn the steering wheel to the left, the stereo loses power.

It's not tied into anything strange for the stereo install, I bought the correct Metra/Scosche harnesses and connectors and whatnot. At one point it was off for so long that I grabbed my tilt lever and when I wiggled the wheel up and down a little bit the stereo came back on again. For the time being, in the interest of not frying an expensive stereo, I pulled the fuse to that circuit. I do recall that I've always had a couple nagging DTCs that I've never been able to track down, (mostly due to lack of effort on my part because it didn't seem to be causing any issues with how the car operated), and one of them is for a short or grounded circuit with some steering sensor. I'll got out later and pull codes to get the exact one. Just thought I'd start this and see if anyone has any ideas or suggestions.

I'm guessing that somewhere in the column some wires have become exposed due to age and wear and when I turn the wheel to the left something is shorting/grounding out and causing those DTCs to set, and now causing issues with the stereo. I'll probably pull the stereo out at some point to double check that nothing has become loose or damaged back there, since it was a rather tight fit to get the wiring and everything else to fit. So anyways, who has the magic solution to my problem?
 

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That's my guess. Something is loose enough or close enough that when turning, it shifts it's position and shorts out or disconnects. Since you are not blowing fuses ... I'm thinking disconnects. Reach under the dash (with the radio on) and just jiggle around a bit carefully and see what you find.
 

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Discussion Starter #3
Sort of an update, new question-ish. Still haven't resolved this, had to deal with the transmission late last year and by the time that was dealt with it was winter and I didn't feel like trying to tear apart the dash looking for bad wiring in the middle of winter. The issue seemed to be getting worse, possibly due to the cold, or not, but it was happening so frequently (but mostly only when turning the wheel to the left) that I finally pulled the fuse for the radio circuit to avoid damaging that. I also noticed a couple times when it was particularly cold that I could hear an odd noise coming from behind the dash, from approximately the left corner, either like a relay rapidly opening and closing or the snap of an electrical short. And again I also notice it more often when turning the wheel to the left.

Aside from that the car still seems to be working fine, aside from my battery being drained if I let it sit for more than a couple days in the cold, so everything is pointing to an electrical short of some sort that I just need to track down. Someone else had PM'd though and seemed confidant that nothing with the steering column should be tied into the stereo system, at least on B-bodies. However in researching some information on the CCM in the Fleetwoods for a different topic, I became curious if the two systems could somehow be in cahoots with each other through that. I know the CCM handles a lot of different things, including the speed sensitive steering system so maybe the short is sending some sort of feedback into the CCM that's momentarily disrupting power to the radio?

I don't know, just spit-balling really and looking to see if anyone else has any ideas or theories as to what's going on. We're getting close to warm weather though and hopefully soon I can spend the time to track down what circuit is generating my parasitic drain, see if it has anything to with electrics that are a part of or at least attached to the steering wheel and/or column, and then start tearing into the dash to see what I can find.

Side note: anyone have a good recommendation for a testing unit when looking for parasitic loads? I have a cheap, basic digital multimeter, but it will only handle a max 10A load and I'm not comfortable with trying to use that in between the battery and a battery cable to monitor how much load is on the system, especially with everything that initially wakes up when the power is first reconnected. I do enough electrical stuff on both cars and homes that I could justify getting something much better, but not really familiar with what I should be looking for.
 

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Count Your Blessings -

Friction on wiring, wiring getting brittle, and MOSTLY ground issues rearing their head are pretty common for ghosts you are describing. Think how much worse it is for most other guys having the car actually die or not start, compared to a wonky radio. Depending on installation method I wouldn't be too quick to discount the problem being there.

After you read everything you can in the FSM (CCM and the rest), then comb the forum and attend all known ground gremlins, and then finally what I'd do is pull the whole dash apart as much as possible yet still stay driveable and hunt for symptoms with as much exposed as possible. I had an issue come up years ago the cruise would cut off with a left blinker. That lasted 4 years and then neever happened again 5 years ago. And sometimes cruise still won't resume --- and it's the old, "turn off the key / wait til the motor stops / and restart / and all better.

You wanna feel sorry for someone, feel sorry for me. My new FWB has just a cassette radio. And the dam thing doesn't have the decency to just stop working so I'm saved from having to listen to the crap radio! I'm doing a crowdfund for a Nexus 7 any day now.

Seriously, you can pull the firewall connector under the steering if you think the sensor/potentiometer is somehow the cause.
 

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It is probably NOT a short, or you would blow a fuse. It is probably a connection, or a break in a circuit. Sometimes complex circuits have a relay stick, and part of it does not shut down. If it takes a couple of days to drain the battery, you can probably use your multimeter safely between the battery and cable.
 

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Discussion Starter #6
Friction on wiring, wiring getting brittle, and MOSTLY ground issues rearing their head are pretty common for ghosts you are describing. Think how much worse it is for most other guys having the car actually die or not start, compared to a wonky radio. Depending on installation method I wouldn't be too quick to discount the problem being there.

After you read everything you can in the FSM (CCM and the rest), then comb the forum and attend all known ground gremlins, and then finally what I'd do is pull the whole dash apart as much as possible yet still stay driveable and hunt for symptoms with as much exposed as possible. I had an issue come up years ago the cruise would cut off with a left blinker. That lasted 4 years and then neever happened again 5 years ago. And sometimes cruise still won't resume --- and it's the old, "turn off the key / wait til the motor stops / and restart / and all better.

You wanna feel sorry for someone, feel sorry for me. My new FWB has just a cassette radio. And the dam thing doesn't have the decency to just stop working so I'm saved from having to listen to the crap radio! I'm doing a crowdfund for a Nexus 7 any day now.

Seriously, you can pull the firewall connector under the steering if you think the sensor/potentiometer is somehow the cause.
I certainly haven't discounted the possibility of the radio install itself causing that issue, it just seemed to only occur when I turned the wheel. I opted to just pull the fuse for the time being to protect it, since I had no interest in trying to pry off that 20+ year piece of fake wood trim when it was 20° or colder outside.

I wasn't aware that there's something I can disconnect at the firewall for the steering sensor, I may have to look into that and give it a try and see if anything acts differently. I have nothing against the speed sensitive steering system, I just wish it was something we could tune or adjust to our preference since it's overall too easy to turn the wheel and gives vague if any feedback.

It is probably NOT a short, or you would blow a fuse. It is probably a connection, or a break in a circuit. Sometimes complex circuits have a relay stick, and part of it does not shut down. If it takes a couple of days to drain the battery, you can probably use your multimeter safely between the battery and cable.
I think I have a minuscule leak in one of my original rear air shocks though, so whenever I disconnect power and reconnect, I never know if the pump is going to kick in. At the very least I would need to pull the fuse for that system before trying anything. I just wasn't sure if I would exceed 10 amps when all the computers wake up and interior lights come on, since I need to leave the driver side door open until the computers all go back to sleep to see how much actual parasitic load there is and then start pulling fuses to see what circuit has the drain.
 

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To prevent ampmeter overload use a wire to short the meter's test probes together. When you think the systems are asleep remove the shorting wire and the meter will then be able to read the load.
 

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If your headlights are off, the startup current is close enough that if the fuse in your meter is a typical slow blow type, it will be happy. But an easier way is to wire the meter in series and then put a jumper across it temporarily. Wait for the car to come on and settle and then remove the jumper. The meter will read under 10A and be happy.
 

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On my '94 Fleetwood,

... I do recall that I've always had a couple nagging DTCs that I've never been able to track down, (mostly due to lack of effort on my part because it didn't seem to be causing any issues with how the car operated), and one of them is for a short or grounded circuit with some steering sensor. I'll got out later and pull codes to get the exact one....
Is the MIL light on, or did you just see codes in the HVAC? Anyway, you really should attend to all known issues to reduce variables.
 

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Discussion Starter #10
I have rejoined the world of the living, got taken out for a few days by a chest cold, over the weekend no less. Nothing like spending your entire weekend in bed coughing your lungs out. Finally feel decent and clear headed again so figured I ought to catch up on here. I like the idea of a jumper wire to hold the load until everything settles down and then just remove it and start taking readings from the multimeter. However I stumbled across a much easier method the other night, from a popular youtube mechanic, I'll add it at the end.

As far as MILs, nope, never. They work, they light up when you first turn on the car, but nothing has ever been serious enough for the computer to put on an idiot light. I now seem to remember getting into this back when I was trying to get into the PCM so I could datalog and program, but without running out and pulling codes, I believe the two recurring ones are for a short/ground/something in the steering wheel sensor circuit, and a short/ground/something in the courtesy lamp circuit. Steering wheel circuit would seem to play into a lot of what I'm experiencing, but I don't know why the courtesy lamp circuit would be involved, unless they share something common somewhere.

Well, actually unless I'm mistaken both would be involved with the CCM since that handles the adaptive steering and retained accessory power. And the stereo would also then be involved since it's also tied in with the retained accessory power system. I need to pull the codes, pull out my FSM and start familiarizing myself with the checklist for dealing with the codes that are coming up, and once I get a few warm days in a row I can finally start digging into this.

And here's the parasitic test video I found. Never would have occurred to me to test it this way, but that's usually the way it is with me, the easier and more obvious it is, the more likely it is that I'd completely overlook it. I also like that there's no pulling of fuses involved, you just have to wait for everything in the car to go to sleep. On the Fleetwoods, I think that takes less than 20 minutes? But I'd probably give it at least double that just to be sure.

 

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Discussion Starter #12
I do plan to find a better meter, mine is one of those $10 ones you find at the auto parts store, bought it years ago when all I needed was a cheap, basic multimeter. These days though I've learned to do a lot more and can justify something better. And as far as I'm aware the wipers work fine, never noticed any abnormal behavior.
 
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