Hello all. Hope you are well and cv-19 free. I have been having a no start/start with my 740. Fortunately I have another car that I have been using and I am taking some time from my other projects to address the issue. I have a flow sheet that I downloaded a few years ago for troubleshooting and I started by checking the condition of fuse 1 and 11 which are fine . The voltage at lower pin of fuse 1 shows battery voltage (12v+).
I could not get 12v at the lower pin of fuse 11 while cranking ( as directed by the downloaded trouble shooting guide) Interestingly though while cranking to check for this voltage the car started and ran! Let's back up . A few years ago I had a similar situation and found that there was corrosion at the connector behind the carpeting above the left wheel well . The large pink wire ( 12v to pump during run mode ?) was the culprit so I bypassed the connector totally for that wire alone . In addition I also ran another wire from a 12v source on the fuse box straight to the pump via a switch that I installed as a back up.
Now to the present. While the car is running I reinserted fuse number 11 and it continued to run. ( so what is connected to this fuse?) I then proceeded to shake the entire fuse block assembly and the car shuts off. Now I am thinking that I need to remove the fuse box assembly for closer inspection and so that will be the next challenge . Hope there is something in the faqs for that. Will update then.
Cheers
Paul