This is a follow up article from battery & alternator diagnosis for those you with a new body style Saab 900. As I mentioned in my first article NG 900, 9-5 and 9-3 have computers that stay active for up to 20 minutes after the key has been removed from the ignition. When performing the drain test on these cars follow the instructions in the first article to hook up your amp meter, and wait 20 minutes to check for your actual drain at rest. This following article will detail some of the going ons during that 20 minute shut down for the new body 900. I will also outline a more detailed test procedure to help you find those hard to find battery drains.

Warning only perform this test in a well ventilated area and wearing safety glasses. Removing your battery cable can cause sparks that can ignite explosive gasses given off the by the battery.

Test procedure A) First thing is to have your Radio code, then turn on the ignition switch, your radio and ACC climate control.

B) Roll down the drivers side window open the hood and close all doors. Then reach in the drivers window and remove the key from the ignition switch, and wait for interior light to go out.

C) The next step is to hook your amp meter in line on your negative battery cable without breaking the connection. (This is very important not to loose power to the vehicle. The type of problem we have seen in the past is the radio, amp or acc will drain when the power is turned off at the ign but will stop if all power is interrupted. This is why we must perform this type of test.)

D) Hooking up your amp meter will be tricky try this method. Loosen the battery cable slide the terminal upward connect your amp meter lead to the exposed post under the terminal. Connect other meter lead to terminal remove terminal completely from battery post. If during this procedure your interior light comes on you know you have broken the connection start over.

E)Now you wait it out and monitor. This is what you should see on a good vehicle.
480-420 ma from acc 4 min
300 ma from trionic 15 min
80 ma from ICE 20min
After 20 minutes you should have a reading of 20 ma

If you find you have a higher than normal draw this is now the time to do further diagnosis. To do this we will disconnect items and look back at our meter to see if that was the offending unit.The first thing to look at are the most common cause of battery drain on the 900 model. 900 se models have problems with the radio amp try disconcerting the power supply to this item. ACC panel have also caused drains.

If these items are not a problem pull every fuse one by one checking the meter every time when you get to a fuse that lowers the drain to normal check the items on that circuit.