failed thermocouple

The sdl system is a cat protection circuit. If your issue is in the system and not truly an overheated cat there is no problem driving it. The problem is of may be that a faulty blinking light can turn into a faulty solid light and a bank shutdown which makes driving it not a good idea.

Make sure your cats aren't overheated with a laser temp tool. If they aren't then decide if you want to take a chance that you don't get a bank shutdown.

Troubleshooting and resolving the sdl is posdible if you are hands on at all.

 

if your getting sdl flashing at cold start it is obviously not cat temp related
it is likely a bad thermo probe
or bad cat ecu. more likely the cat ecu then the probe.

also if you had an engine out done recently make sure you don't have a bad ground in the wiring of your engine ecu. often wiring gets sliced when pulling it through fire wall when engine is dropped.

 

As I said above in answering your original question which was can you drive the car with a blinking sdl 45 miles, yes you can but your blinking sdl could turn to a solid, bank shutdown sdl and that is not a good thing to be driving any distance on.

FYI , I had this exact experience and it was a faulty thermocouple, intermittently causing a solid sdl and bank shutdown.

You can have sdl lights with no obd codes as well.

Most likely you have a faulty detection system and not a hot cat.

 

I had basically the same issue with flashing SDL and then it went solid and dropped a bank on my 355, so I stopped at a local spot and waited 30 minutes ish. No light and everything was fine. Went to visit a friend and after an hour or so hanging out when I felt my leash being tugged at I went to leave and the SDL was on solid at start up and after 5 seconds or so a bank shut down. I left the car in my friends garage etc. This forum has definetly helped with ideas and what to check, and as a hands on guy will be trying to determine the issue. All OEM exhaust and cats by the way.

 

The best way to troubleshoot this is get a DVOM and probe the output leads of the SDECUs. At cold dtart up they should be .5v and gradually get to 3v when fully heated. If it is happening right at start up, a static measurement at that point may be enough. If it is more intermittent you may have to tap the outputs with a lead in your cockpit and dirve around with the DVOM and see what voltages you are getting.

Once you determine which side is the culprit you can start switching components around and determine which part is faulty.

 

Dr. Bob, I appreciate your insight and have been reading your posts on the subject with other Ferrari Chat members. I value your opinion and insight.
Thanks
Mark

 

My car came with a removed SDL bulb, and a bad ecu & TC. Bob was very helpful getting it sorted and teaching me about the system. Once you learn how the system works, it will make sense and becomes pretty easy to diagnose. DrBob also makes TC, I bought one and the fit was perfect and the price very fair.

 

I experienced a blinking SDL light last year upon start up. It happened out of the blue and it was clearly not related to heat since it occurred when the engine was cold. No CEL. It happened randomly for a few drive cycles afterwards. Very intermittent.

Per another thread on Fchfat I did some troubleshooting with my multimeter, using very small paperclips as jumpers into the thermocouples' connectors. All readings were normal--and I never experienced another issue after that.

My belief is that inserting the paperclip into the female connector slots removed oxidation and "cleaned" the contacts, providing a more solid connection when I reconnected them to the ECU's.

You might want to try this before throwing parts at it.

 

I had the same issue with 99 euro F355 for a 12 month period. Intermittent SDL, hot or cold, immediately or after driving for hours, sometimes blinking sometimes solid followed by bank shutdown, sometimes SDL went out on its own.
Checked thermo's, all ok. Replaced ECU's (cases cracked anyway) , no change.
Eventually battery failed and would not charge. Replaced battery and have never seen another SDL since. Either battery connection was dodgy or battery cells were breaking down leading to spikes in power to Engine ECU?
Worth checking battery.

 

Thanks all. I am on vacation mini vacation in San Antonio Texas now but plan tobtrouble shoot once I am home. Battery will go dead after two weeks of not driving. I should never not drive for two weeks . I need my fix. Thanks for all the advice. On a side note, you should have seen the look on the guys faces at home Depot when I picked up some plants?????? The boys were freaking out. It is infectious ! !!
Mark