I have a 2001 Saab 9-5 2.3 turbo with auto transmission, 92k miles. For the past 8-10 months, I’ve had the issue described below. My new mechanic shop, a Saab specialist place, states they have a total of 3 cars with same issue and they are stumped…so is my old mechanic.
PROBLEM: I drive the and warm up the engine, it always starts cold without a problem. I turn the car off after a drive, go into a store, etc. and then come back out in 10-60 mintues later when the engine is still warm (ambient temp is always >50f when this happens). I turn the ignition key and get just a single click, no engine trying to turn, no cranking, etc. All the dash lights come one, etc. Everything is normal except the silence when the engine should be starting. I then have to sit there for 10-60 minutes more and wait for the car to cool down to restart.
My first mechanic was positive it was the ignition module as he said he duplicated it. This was replaced along with the relay. This fixed it for about a month, then it started again. That part checks out fine still according to the new shop.
The new shop has spent hours looking over this car and others like it. When it won’t start, putting it into neutral won’t change a thing, so the neutral safety switch appears to be okay. The checked the starter, battery, alternator, etc…all check out. They ran the factory diagnostic computer and found nothing.
In an attempt at something, I suggested that with heat, maybe an electrical connection was swelling, thus terminating the connection until it cools down. With this in mind, we found the main wire that connections the ingition system in the cabin to the engine area (sits on the bulk head). The new shop removed this wire and made a hard connection between the two, eliminating the possibility of this heat issue on the connection. It appeared to work for about 2 weeks and now it’s back again, worse than ever.
I love this car. I don’t want to sell it. I need something that will start reliably! ANY suggestions are welcome!!!
I’ve put quite a lot into this car in the past year and would like to keep it. New tires, the ignition switch/relay, 2 new engine mounts (old ones were broken), fixed the cruise control, new brakes and rotars, shocks/springs, etc. And it’s paid for 
That’st he best part, so a little maintenance is not an issue.
They also looked at the theft system, reset it to factory default - no change. Also tried my other key too. No change.
I should specify that clicking sound when starting. It is just a very faint sound when the key is turned, it sounds like it comes from the ignition inside the cabin…nothing in the engine area.
I have the same issue from time to time on my 2001 9-5 Aero. My local Saab genius said it is likely the Neutral Safety Switch (also known as the Transmission Range Sensor). He said the way to confirm that is when it won’t start I should pour a bucket of cold water on the hood right above the battery area since this sensor is under the battery. If the car instantly starts after that then you know it’s the Neutral Safety Switch.
A way to know if it’s something ignition related is to try holding the key in the start position. I’ve found that holding the key cranked all the way over will often get the car to start after 5-10 seconds as opposed to waiting 10-60 minutes.
I love my Saab too and am willing to put up with the small maintenance items for this car. And I’ve been fortunate to have minimal issues with my Saabs.
I hope this helps!