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Battery swap oops!

2K views 10 replies 3 participants last post by  HiddenBunker 
#1 ·
Hey guys, need a little electrical help here..

Did a stupid thing, had a dead battery and used a donor battery to keep her running. the stupid thing was that the terminals were opposite and didn't notice until I got sparks! ugh.

I immediately hit myself in the head with a ratchet, so no further hazing is needed. :p

I replaced a few fuses, radio and other minor stuff. no major fuses or links got blown. I am having some issues though.

specs: 97 9000 cse turbo

When I turn on the ignition switch and put it to the "on" position without starting, all seems fine for a few seconds then I get rapid clicking of what sounds like several relays clicking rapidly from under passenger air bag fuse box. Once I start her up the relays become quiet.

It will start and run! but, before it gets warmed up, I am getting a erratic idle. hunts up and down like a faulty IAC valve. Once it gets to operating temp it seems to Idle smooth with no real driveability issues.

I am also getting an tachometer jumping issue once it gets above 2k rpm.

I was doing a bit of searching and some of the issues seem to point to an ignition switch failure. what I also need to do is clean all of my grounding points that I can easily get to. what other suggestions should I be trying to do. I will check my supply of spares for relays and try and do some relay swaps to see if I killed any of the relays in the relay block under the pass side airbag location.

Any help you guys can come up with I would be greatful!
the current battery that is in it is running at 100% and the dash volt meter says the alternator is putting out 14.5 volts so that seems good. no other issues, all locks and alarms work ect.

David.
 
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#3 ·
from what I understand TCS is only in 93-94. mine is a 97 cse.

Today I reworked the stock cable terminals for a new set. cut the cables and cleaned them and installed the fresh terminals. Reworked the the ground to the manual trans. also cleaned all the ground connections in the engine bay that I could see.

(battery ground strap to trans, ground on the drivers fender, engine ground strap at the top torque engine mount, opened the cover where the computer is and did the ground strap on the computer.)

Still had all the issues, clicking relays, erratic idle, and tach jumping. although the idle issue did take far less warm up time to settle down.

I am not using her as my daily driver at the moment, and I was only able to put in an hour or two today.

keep the help coming guys!
David.
 
#4 ·
My gut says you did some damage to the ECU, though the extent of the damage is unclear.


The ignition switch is easy to test, as 1) it's in the steering column ;) , and 2) ohming out the contacts with a simple DMM will likely tell you if you need to be concerned. It's pretty unlikely that you did any damage, but it's hypothetically possible.

Did you have the key in the ignition when you made the 'oopsy'?
 
#5 ·
My gut says you did some damage to the ECU, though the extent of the damage is unclear.

The ignition switch is easy to test, as 1) it's in the steering column ;) , and 2) ohming out the contacts with a simple DMM will likely tell you if you need to be concerned. It's pretty unlikely that you did any damage, but it's hypothetically possible.

Did you have the key in the ignition when you made the 'oopsy'?
Thanks for the tips.

Yes I did have the key in the on position.
Ill get cracking on the switch checking tomorow.
would be a bummer to kill the computer.

being a 97 cse, what other years would work? I plan on getting a tune by a local reputable guy in either before winter sets in or in the spring, but dont want to go low pressure.
 
#6 ·
Cracked open the ignition switch today.

Pulled the wheel and all the hand controls, loosened the adjustable column and pulled the bolt then slid the whole lock assembly and upper part of column onto the bench.

Unscrewed the ignition lock assembly from the tumbler case and cracked that puppy open.
You could see where there was a bit of arching at the contact points, cleaned the contacts off with an eraser and then a bit or alcohol, all clean and smooth.

the harness connector looked good. none of the factory solder joints looked bad. had lots of old flux on them though. but all was sound.

during disassembly, I had to drill out two rivets that were into an aluminum block to get to the mechanism, drilled for a new slf taping screw and assembly was then same as reverse.

held fingers then turned key.......


nope, clicking was still there.

I now also noticed that the secondary cooling fan on the grill side of the radiator was running while ignition was set to on switch without starting and the IAC unit was clicking. getting and open then close signal. ugh.

next is to look for more bad grounds or burt wires under the dash assembly. I need to pull my dash pad off for replacement of the cracked one for my new good condition one anyways, so back at it tomorrow.
If I had a spare computer I would swap and test that. Is there a way to crack that thing open? didnt look at it too hard when I pulled it to clean the ground. all the computer pins looked good though.

Thanks,
David.
 
#7 ·
Well you would expect there to be some arcing at the contacts (given the age, and that you were replacing a dying battery), though melted/discolored plastic and insulation would be a dead giveaway of a bigger problem.

It would be helpful to know which specific relays are clicking improperly.

The engine components I would diagnose properly, (in addition to looking at the ECU of course) assuming you can find the specs to test to, would be the Air Flow meter (which has a direct ground), and the Auxiliary Air valve which has a direct ground connection and shares the common hot side of the injectors.

If the Aux Air Valve ohms out as faulty, hypothetically the voltage drop could cause low injector voltage (though the ECU should throw a CEL code if so), but that's not to likely. Further, you would definitely notice this while driving!

I have not torn apart the ECU on mine (yet!), so maybe someone else can comment on it's ease of dis assembly, but I have done several other (non-Saab) cars. While it *may* be a visible vault, a fault is usually not visible. That's why you hook it up to a tester to test that it's outputs match spec. I am curious if you have checked to see what non-CEL codes it is throwing. Your car has an OBDII connector which should work with an off the shelf reader.

Also, you haven't mentioned how it drives? Or if there is any noticeable difference in performance...
 
#8 · (Edited)
Thanks for the input Navar,

I plan on getting into the dash tomorrow(sat) and see what relays are acting up.
I am throwing no codes! clean as a whistle in that department.
idle is rough until it gets up to operating temp, then she runs great! pulled 7sec. to 60 just yesterday with 6.5 psi of boost, was trying to reset my base boost pressure from the other engine work I was doing...

and before you say, hey what work were you doing.... all work was done and running fine on that weak battery with no issues, just wouldn't hold its battery charge, so I swapped it with a spare battery I had and all went to hell after I got the sparks!

Someone also suggested a DI cassette, so I will put my spares to work on that suggestion.
I will also check the ohms on the IAC. I have no mass air in the 97.
 
#9 ·
Soooooo.

Started with some engine stuff today, swaped DI cassettes, and put the ohms reader to a few parts under the hood. No luck there.

Pulled apart the dash and started pulling relays. needed to replace a few trim parts on dash anyways...

While in the dash I figured I would pull all the fuses again just to double check....

fuse 23 engine system computer management... 5 amp little bugger. yep, blown. could only see it when I held it up to the light. ugh.

So, after my rooky mistake, all is back up and running as it should!
 
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