rbuswell

Did the wiper reversal project from Wayne Dempsey's book. Everything seemed to go very well. Was careful to make sure wires didn't get involved when returning heater box to it's place. Put everything else back together.

Now the O2 light and the battery/alternator light both come on and stay on. Took out heater box again and don't see any pinched wires or anything pulled loose. Nothing seemed even close to the area where the box belongs.

Any wiring schematic experts out there who can help me chase this down? Thanks.

rbuswell

Anyone have a theory why both the O2 light and the battery/alternator light would both come on after this project? I still haven't found anything loose or broken.

rbuswell

Not sure why I said O2 light but I meant OXS light. Another note ... the car seems to start and run normally otherwise. Just the two lights come on and stay on. Bentley manual talks about the alternator light coming on and staying on when under high load, in other words when there is a short of some sort. Ideas of where to start looking?

theiceman

I haven't read the bently but I would not assume "high load " means short. just a load high enough to exceed the capacity of the alternator and so the battery starts being consumed therefore a light ..
anyway lets start simple. start unplugging fuses until the lights go out and see if you can see which circuit is powering it. Also stick a meter on the battery while running and verify the voltage put out by the alternator. if it is above 12 ( 13 - 14.5 ) volts the light is false. If it is around 12 something is genuinely affecting the charger circuit of your car. I don't know what a OXS sensor is so I can't help their.

I will check the bently and see .. what year is your car ?

rbuswell

I was beginning to wonder if I'd done something to offend the group. No answers in three days on either Rennlist or Pelican. My car is a 1982 SC Coupe.

The OXS light is the red one between the speedo and tach on the upper dash that lets you know that the Oxygen sensor is either not operating or over the 30k replacement cycle. Just flipped 80k miles so the 30k cycle shouldn't be triggered. There's a reset switch on the back of the speedo that you only use at the 30k cycle points to reset, theoretically after you replaced the oxygen sensor on the cat pipes. There may not be one on the ROW cars so you may not have one if yours isn't a US car.

One thing I'm unclear on is whether that means since the last reset or at 30k, 60k, 90k, etc. odometer flips. If it's since the last reset, that could explain the light coming on since I don't know for sure when the last sensor was replaced. The car hadn't been driven at all since I did the wiper reversal, so there shouldn't have been a chance for the switch to engage, one would think, since there was zero new miles since I did the project.

Peter Zimmermann

rbuswell: I haven't offered my 2 cents worth because I don't have the foggiest idea what a "wiper reversal" is. That said, the OXS light counter can be reset at any time. The button is not on the speedo, it's on a small box located just forward of the speedo. You must pull the speedo out to access it, once you can see it you'll be able to see the white reset button on the rear facing surface of the box. Use a long skinny screwdriver to push in the button, gently, until you hear a click or similar faint noise. Release the button and start the car to check. That combo of batt/OXS lights being on usually can be something else, but reset the counter first.
Pete

Lorenfb

"I haven't offered my 2 cents worth because I don't have the foggiest idea what a "wiper reversal" is." - Pete Z -

That's it! Especially when wiring is modified (Mickey Mouse), e.g. alarms & etc.,
which are read about in questionable books, i.e. non-Porsche factory manuals.

autobonrun

I was in a similar boat.

I didn't offer any advice because I had no clue what the OXS light was since my 79 doesn't have it. On top of that, I thought the wiper reversal was a purely mechanical fix so that the wipers come to rest on the passenger side giving better visibility. I couldn't associate that change to a wiring problem.

http://www.pelicanparts.com/techarti...r_reversal.htm

theiceman

The wiper reversal is simply to switch positions on the wiper arm so they "rest" on the passenger side not the driver side. Theoretically there is no wiring. but you do going where the wiper mechanism is behind the instrument panel so the wiring is suspect.

RB don't take offense if people don't respond , sometimes it is better to give no advice as oppsoe to the wrong advice. I have a 78 so no oxygen sensor. i really do think you have disturbed a wiring harness but start with the tests I recomended and lets see where you are at. I have a bently so I will check the 82 wiring diagram for you . But in the mean time if you can get the info I asked you about it would help. PS did you try resetting the switch . ? what have you got to lose. ?

ice

theiceman

Okay i think I have something ... The gen light is connected right to the oxy light . so this makes sense.. is your speedometer working ? that is in the same circuit...

the only part I am not sure about is the doteed line wire from the ignition switch to the generator light (red/black) comes out of there as blue/red and goes to the oxy warning light . comes out as red and goes to he oxy millage switch, comes out as red/ blue and goes to speedometer , comes out as red/ black and oes back to ignition switch. Check these first.

rbuswell

Busy week. Also, I've been a bit intimidated to touch anything since this seems to have such a high correlation to the heater box being moved out and back in for the wiper resting point switch over. I haven't driven the car since I wasn't sure if I'd burn something up by not solving the short quickly. The car has a past of wiring trouble, but many years ago.

Therefore, can't answer the speedo still working question, Iceman. I will check the wires you suggest first. Which page of the Bentley was the diagram you looked at so I know we're working off the same page?

Sorry for the lack of precision in the description of what I'm up to Mr. Zimmerman but this was what I'd expected to be a no-brainer ... to get the wipers to rest on the passenger side, as the Wayne Dempsey Project 69 described. There is no wiring involved in the project normally and I thought I took great care to put everything back without jarring anything. Obviously not.

Based on the comments, there doesn't appear to be any downside to resetting the clock on the OXS switch other than losing the 30k miles count. I was aware that the reset was other than on the back of the speedo but found that out after I wrote my earlier post. I'll try to solve the short before I do anything with that.

I wasn't offended by the way ... I was nervous that I'd messed up the best way available to keep my car in tip top condition. You'se guys are the best!

theiceman

large sums of money can undo any damage so don't worry ,,:-)

rbuswell

Popped out OXS light housing, oil/alternator gauge, tach and speedo. No wiring abnormalities that I can see. Also reset the OXS mileage counter but the OXS light stayed lit and so did the alternator light.

One possible hint ... when I rev the engine, the two indicator lights in question begin to dim somewhat.

theiceman

970-9 is the page..

souns like toue 12v might be biased low. causing a drain on the battery. check that alternator output.
take it round the block and check the speedo to verify the circuit we are talking about ..

rbuswell

Drove around the block. Speedo worked and appeared to be accurate. Both lights dimmed in tandem and almost all the way out at around 30 MPH.

Trust me on this ... it has never done this since I owned the car and I didn't adjust anything. I only did the wiper reversal project. It just seems bizarre/unlikely that the alternator would now be acting up and/or failing just because I had the heater box out. Would you agree?

Another new development. The car has always had a very faint click that I associated with the speedo because it sped up as the car did. With the heater stuff out of the way and the speedo not all the way in it's housing, the clicking is much louder. I wonder if it could be the mileage counter clicking instead of the speedo now that I reset the counter. Speedo had been in to North Hollywood per PO about 20k miles ago.