Saabscene Saab Forum - Saab Technical Information Resource banner

1 - 5 of 5 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
My wife was driving her 1999 9-3 covertible on the motorway when suddenly all the instrument lights went out. The engine continued to run OK and the exterior (driving) lights were working. She called me and I told her not to switch the engine off, which was just as well because when she got home (after driving a further 100 miles or so) the car refused to start again. We have tried to start it on several sucessive days with no luck. Now the lights on the dash behave as you would expect when the ignition is turned on, but the engine fan starts immediately (even though the engine is stone cold) and runs for several minutes. I think the engine fires for a split second when it is turned over, but it won't run (and if it fires it really is for only a fraction of a second, so I can't be sure it actually does fire). I have tried to read the fault codes but the set-up I have won't read them (that is the subject of another post, "1999 9-3 Can't read OBD2 codes on 2.0 9-3 convertible"). Has anyone experienced this before? The fact that the fan starts running every time I try to start it makes me think perhaps the engine management unit thinks the engine is hot and is providing fueling for hot running, although in fact it is cold. I have tried starting it with the throttle depressed to deliver more fuel (normally this is not needed) but it didn't make any difference. The car is a 2 litre non-turbo.
 

·
Registered
Joined
·
18 Posts
First off...'cracking' the throttle during a crank cycle won't give you more fuel in these cars.
As to your issue of no start with no dash lights....Check fuse 35 and fuse 17 in the main fuse box at the end of the dashboard..
Fuse 35 should be hot at all times and 17 get a +12V source when the key is turned from the on position to the start position.
That source comes right through the ignition switch, which also sends a +12V source to Fuses 6A, 9, 18, 19 and 24..
The main power into the ignition switch for this branch, is by way of the #3 MAXI fuse (big fuse) in the fuse holder next to the battery.
If none of the fuses mentioned earlier have power on crank and the MAXI is good, then chances are a bad ignition switch.
Good luck.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
Hello APC900 - thanks for your detailed reply. I've just done tests along the lines you suggested and fuse 35 is live at all times. There isn't a fuse in position 6A on my car (a UK spec convertible) but fuses 9, 18, 19 and 24 all go from 0V to 12V when the ignition switch goes to the ON position (not from ON to START). In addition I removed and checked every fuse in both fuse boxes and sprayed the connector bases with an electrical cleaner. When testing the voltages one of my leads was earthed against the door retaining strap from which I conclude the chassis earthing is OK. I also checked the earth on the cylinder head and earthing point on the chassis; all were good, and anyway the engine turns over without hesitation so the starter motor must be getting a good earth.

From these tests, would you say I have eliminated the ignition switch as the source of the problem, or have I simply eliminated some, but not all, possible ignition switch errors?

A couple more points that may be relevant. I noticed when I was running the tests that all the instrument warning lights behave as you would expect when the ignition key is turned to ON (I reported this in my original post) and in addition the information panel reports that it is going through its checks and then reports "CHECK OK". If the ECU were faulty would it still report "CHECK OK"? As my next course of action is likely to be replacing components in turn until I find the faulty one, and I think I have already eliminated the ignition switch as the cause, I wonder how reliable that "CHECK OK" message is with regards to the state of the ECU. I did a few other general checks and found the distributor cap and rotor arm are not in great condition, so I will replace them before I do anything else, although I don't see how that could have caused the loss of instrumentation lights which was the first symptom observed before the car stopped and then failed to start
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
Update - rotor arm and distributor replaced this evening but it didn't make any difference. Well, it made a small difference in that I am now confident the engine does fire for a fraction of a second when I try to start it, whereas before I couldn't be sure so I assume when the car does finally run again it will run better than before, but it still won't start.
 

·
Registered
Joined
·
18 Posts
You mentioned replacing distributor parts in your second reply. I missed the last sentence of the original post....sorry.
 
1 - 5 of 5 Posts
Top