Amur_

Hey!

When I shift into reverse, I get a drop on my voltmeter of 1-2 volts. At night, my lights dim (slightly) and everything. Is this normal and if not, where should I look to fix it?

My girl's an '86 manual GXL...


ttyl,
Amur_

cymfc3s

thats because the reverse lights come on, you will see a drop in voltage.

Amur_

>>thats because the reverse lights come on, you will see a drop in voltage.

But that much of a drop? That's an awful lot for a couple of bulbs, isn't it? Only the cabin's blower fan has as much of a hit on the voltmeter. It doesn't seem right.

Gene

iTrader: (1)

check the bulbs, one of them might have blown up and is causing a short. just an idea.

Amur_

>>check the bulbs, one of them might have blown up and is causing a short. just an idea.

Good idea. Thanx.

Amur_

Cwaters

sure sounds like a short on that circut....

NCsublime

I heard someone trying to explain before that those certain bulbs require more voltage because they are a special type or something. I don't know much if anything about this kind of thing, but I'm sure there was a recent post about voltage drops with some kind of lights.

BBW

I have the same problem with 87 base. The voltage used to be one or two volts lower when the gear was in reverse. Right now, the symptom is slightly different. When I shift in reverse, the voltage drops 1 or 2 volts momentarily, and then the voltage reading would go back to almost normal.

NCsublime

Mine drops voltage witb my lights, brakes, etc. It's a PITA. Can't wait for the new TPS. I'm sure it will help somewhat. You guys think my underdrive pulleys will cause a problem once I install them?

Amur_

>>It's a PITA.

And what's a PITA? (this better not be like one of those 'butt-for' jokes...)

>>You guys think my underdrive pulleys will cause a problem once I install them?

Depends. There's at least one rotary site out there with underpulley 411, including nasty horror story. Check it out...

http://reganrotaryracing.tripod.com/unxhoror.htm

I haven't had time to inspect/clean up the bulbs yet. I'll post the results when I do.

ttyl,
Amur_

NCsublime

PITA=Pain in the @ss

No, I'll be able to install the pulleys, but was wondering if it would cause problems with the charging system since the alternator will be underdriven. I already have problems with voltage drop when certain things are used such as the brakes, clutch, etc, so I was just concerned about the way it will perform with the pulleys on. I have a main drive underdrive pulley, and an underdrive pulley for the alternator.

Thanks, Derek

P.S. I read that story. I wouldn't even try it if it wobbled at all. Looks like it was a huge mess though.

HAILERS

I think you have a potential problem. I just started my car and turned th lights on. I put it in reverse and saw a voltage drop on a meter on only a quarter volt. I remember a fellow on this site that had a fuse that kept burning out. ICEMARK helped him find the source of the short which turned out to be the reverse switch on the transmission. Its possible maybe for that switch to be drawing too much current???? Always possible. I would'nt stay up all nite worrying about it. How long do you stay in reverse each day(lazy man here)?

Amur_

>>wondering if it would cause problems with the charging system since the alternator will be underdriven

Do a search. There's a fair bit of material out there about underdriving accessories on RX-7s. I'd try a search now for you but I'm already *way* past my bedtime. :P

>>PITA=Pain in the @ss

I'll take PITA over FUBAR or SNAFU any day.

>>source of the short which turned out to be the reverse switch on the transmission

Good tip. Thanx.

>>I would'nt stay up all nite worrying about it. How long do you stay in reverse each day(lazy man here)?

Ooh, don't go there! ;D It's not about how much of an intrusion this irregularity is. It's about having the car at 100% of what it should be. I'm not driving my mom's 8-year-old Tempo here. I go into the garage where I take my RX-7 with questions about the mods I've found on various sites and sometimes they look at me like I've got horns growing out of my head.
"Why the hell would you want to do that? You don't really need that."
It ain't about need, darlin'. It's about survival.
I don't race my girl, and she's a long way from fully-tricked out. But I do dig this car and want to make the most of it.

So that's me. Didn't want to write a speech, but didn't know how not too. 'Nuff said.

ttyl,
Amur_

HAILERS

If it really bothers you, I'd go to the schematics at http://www.iluvmyrx7.com/Technical_I...ice_manual.htm and go to the schematic that says HORN, STOP LIGHTS, TURN AND HAZARD FLASHER LIGHTS , BACKUP LIGHTS. There is a swithch on the left hand side of your transmission. It has two bullet connectors going to it. I'd disconnect them from the switch and jumper them together and see if I still had the same voltage drop. If not I'd get another sw for the transmission. If you still have the voltage drop I'd follow the circuit back towards the ignition switch. Would'nt hurt to look at the schematic and check the ground wires at the backup lights also. That two volts drop seems a bit tooooo much compared with my car. Thats a free, no cost download at http://www.iluvmyrx7.com/Technical_I...ice_manual.htm just download the section your interested in to save time and drive space. Have you checked the bulbs in the reverse lights to see if they are the proper ones? Maybe someone stuck in some that are for another thing and are drawing too much current?

Amur_

Finally got into the back of my car yesterday while I was waiting for the undercoat to dry (6 cans of rubberized asphalt, including what seemed like half a can on the shop floor and on my face... ;D)

There were Koito 1156 bulbs in the reverse lamp sockets. They look like they're new out of the package yesterday (but they definitely ain't.) There wasn't so much as a hint of rust *anywhere* on the socket. Those bulbs being where they are, they've got it made in the shade.

I replaced those Koitos with a pair of Stanley 1156s to see if maybe age is a factor. It isn't - I still get a voltage drop in reverse. I didn't have time to go after that switch that is mounted in the tranny. Next time, after I finish chasing the last of the rust in the right-rear wheel well.

And I'm pretty sure that the ground wire for the rear light clusters are okay (although I didn't check.) I swapped out the entire rear harness this past summer - the GXL harness has the wire/connectors for the AAS, the GX harness does not. (?)

ttyl,
Amur