· #1 Posted July 31, 2017 · Report post The car (2005 450 cab) has sat idle since last fall with a maintenance charger connected. The Optima battery reads 14.7V. Nothing changes when I turn the key. Nothing turns on. Where can I find a flow chart for the complete electrics? Where should I look first? Share this post Link to post Share on other sites
· #2 Posted July 31, 2017 · Report post Just curious if you measured the voltage directly across the battery or from the Positive terminal to the chassis of the car? Share this post Link to post Share on other sites
· #3 Posted July 31, 2017 · Report post I measured from +ve to terminal and to bolt holding ground. I just checked it and it has settled after charger removed. It reads 10.7V. Tomorrow, I'll have it checked and try again with another battery. Sometime I need a jolt to start me thinking. Thanks. Share this post Link to post Share on other sites
· #4 Posted August 1, 2017 · Report post So much for that. I went out today and took another reading. The battery read 14.4V.I get nothing. Even the courtesy lights do not come on. Does anyone know where I can get an electric schematic? Share this post Link to post Share on other sites
· #5 Posted August 1, 2017 · Report post I have posted electrical diagrams here before but sadly, due to the Photobucket fiasco, none of them can be viewed and I cannot even log on to my Photobucket account. Share this post Link to post Share on other sites
· #6 Posted August 1, 2017 (edited) · Report post I am now wondering how you unlocked the car. Do the doors open with the key fob? There is a heavy red 12 V cable running directly to the SAM unit N11-11. It powers many of the devices in the car. Some of the fused outputs on the SAM are switched, others unswitched. Determining if there is 12 V present at the SAM would be a first step in diagnosing this problem. The link below is for the 450 SAM wiring http://www.fq101.co.uk/how-to-guides/fortwo-450/electrical/251-sam-wiring Connector 11-4 Pin 1 is the switched 12V supply from key switch position 1. Edited August 2, 2017 by smartdriver Share this post Link to post Share on other sites
· #7 Posted August 2, 2017 · Report post Being a cabriolet maybe he doesn't lock doors. I don't, the top is worth more than anything I have inside. Nigel Share this post Link to post Share on other sites
· #8 Posted August 2, 2017 · Report post I never locked the car before I stored it. Does the battery main go to the SAM before distribution to the rest of the circuits? Share this post Link to post Share on other sites
· #9 Posted August 2, 2017 (edited) · Report post 14 hours ago, Silver said: Does the battery main go to the SAM before distribution to the rest of the circuits? Yes it is the heavy red cable going to the SAM connector N11-11. For the SAM to be energized apart from the unswitched outputs, a signal from the key switch position 1 must go to the SAM. This is part of the security system. How is the battery in your key fob? The doors must be unlocked with the key fob in order to overcome the immobilizer. Edited August 2, 2017 by smartdriver Share this post Link to post Share on other sites
· #10 Posted August 2, 2017 · Report post I tried both fobs, neither worked. One had 2.94V, the other 2.93V. A new battery read 3.0V. Even with that, nothing. The clock doesn't run. Share this post Link to post Share on other sites
· #11 Posted August 2, 2017 (edited) · Report post 2 hours ago, Silver said: The clock doesn't run. Yikes! I would first look to see if there is 12V on the fused output connectors of the SAM. You don't have to remove the SAM. In the photo, the top bank of four are switched. The bottom 5 are always on. The unswitched ones are provided with 12 V directly from the battery. The 12 V comes from a heavy gauge wire connected to a screw terminal labelled N11-11 on the top side of the SAM. If there is no 12 V on the unswitched terminals, I would drop the SAM and see if there is 12 V on the heavy gauge red wire going to N11-11. Have you removed and reconnected the battery terminals? My initial thinking was that this is a bad ground connection from the battery, but you indicated that you had measured 14 V from the battery positive to ground. Edited August 2, 2017 by smartdriver Share this post Link to post Share on other sites
· #12 Posted August 8, 2017 · Report post The last post on this thread was one week ago with no solution posted. The fact that the clock is not working likely means a bad battery, bad ground or perhaps a bad SAM ground, yet the information provided doesn't corroborate this. I was hoping that the original author, Silver, would post the solution to the problem. Share this post Link to post Share on other sites
· #13 Posted August 14, 2017 · Report post Your battery is dead. Buy a new one ($114 @ dealership) re-install and start the car...on end of the season (cabrio) or if car needs to be stored for prolong time charge the battery and disconnect positive lead. Share this post Link to post Share on other sites
· #14 Posted August 14, 2017 · Report post 1 hour ago, Vulicevic said: Your battery is dead. Buy a new one ($114 @ dealership) re-install and start the car...on end of the season (cabrio) or if car needs to be stored for prolong time charge the battery and disconnect positive lead. On 7/31/2017 at 4:09 PM, Silver said: The car (2005 450 cab) has sat idle since last fall with a maintenance charger connected. The Optima battery reads 14.7V. Nothing changes when I turn the key. Nothing turns on. Where can I find a flow chart for the complete electrics? Where should I look first? Above is the author of this thread's first post. I tend to agree that the problem is a dead battery, but that isn't supported by the information provided. Share this post Link to post Share on other sites
· #15 Posted September 22, 2017 · Report post How stupid and embarrassing. I miss read the VOM. It was 1.3v not 13. I had an old Optima that was the wrong one in the basement. I bought a longer ground cable, finally got around to changing the cable and installing the old Optima and the car started immediately. This is after sitting for about a year. Now, I have to clean or change the crankshaft position sensor because the car will not start after running for a while. Thank you all for your forbearance. Share this post Link to post Share on other sites