Wiper fuse keeps blowing, automatic transmission

[euromobile900]

Hi all,
I'm working on a friend's 1998 900 S, with automatic gearbox. The wiper fuse keeps blowing, every time he turns on the wipers. I'm fairly unfamiliar with the NG900, so some troubleshooting help would be appreciated. From forum searches on SaabNet, I have gleaned that the wiper fuse usually blows because of a faulty reverse light switch on cars with a manual transmission. They say to pull the wires to the switch and see if the problem persists, but no mention is ever made of how to go about troubleshooting if it's an automatic, which has no such switch, instead having a range-switch that combines a whole bunch of functions. Even a scan (or photo) of a circuit diagram would be much appreciated, so that I have some idea where to start.

Thanks!!

[Shazam]

From the searching I have done, people have basically come the conclusion of:
1)Check all the lights in the back, even the ones for the license plate.
2)If it's not 1, then basically you have to buy a new neutral switch, which is upwards of $300.

When I get home I'll check my Haynes and see if it has a good wiring diagram.

[euromobile900]

1)Check all the lights in the back, even the ones for the license plate.

What exactly am I checking them for? Short circuits? Burnt out bulbs? And does this extend to the brake lights too?

When I get home I'll check my Haynes and see if it has a good wiring diagram.

Thanks for looking this up for me. I'm a bit out of my league here, but I owe this guy a favor.

[Shazam]

From what people have said, burnt out bulbs basically. I have no idea how a burnt bulb would cause that, but it's what some have said on that other forum.

Can't find my camera, so I'll have to scan them when I get to school. But I think two or three of the wiring diagrams might be of help.

[euromobile900]

Interesting, and worth a shot anyway! I know some lights are burnt out on that thing, and with luck that is the problem. If not, the wiring diagrams should let me address the issue. Chances are, this guy is not going to want to buy a new $300 range switch (I was afraid that might be the problem) so I'll likely be cutting and soldering in some sort of manual toggle for the reverse lights until I can get to a good junkyard to grab proper parts. Car is a crash victim, needs a new hood, and I think he got it for about $300 in the first place. That said, the owner is impressed with his SAAB experience so far. He said he was amazed it had 175,000 miles on it and did not burn oil yet...but he IS a honda guy.

[Shazam]

Finally able to get them. Here they are, I hope they help. Let me host them separate so you can get a better view.

[Shazam]

[euromobile900]

Thank you for the wiring diagrams! The guy now says it only blows the fuse when he operates the wipers, so I think I can conclude that (strangely) there is some short in the wiper circuit. It may be the first NG900 ever to have this problem. For now, I gave him this guide to fuse replacement:



Just kidding. He is going to use his Honda in the rain until I get there to find out where the short is.