Engine Shuts off and Restarts Immediately in the hear 2004 V70 2.5T

[leftyref56]

I have a 2004 Volvo V70 with a 2.5t engine. It has 276,000 miles and has developed a recent problem, While driving the engine acts as though it misses a beat, but actually acts as if all electrical power shuts off and then immediately comes on. This only happens when the outside temperature is above 85 degrees Fahrenheit, Sometimes it shuts down the dashboard and the car struggles to accelerate and I have no window or electric locks.
I disconnect the battery and the dash and accessories begin to work again.
What should I be looking at to correct this situation?

Bob
2004 Volvo V70 2.5T

[jonesg]

Does the electric radiator fan come on, what temps is it running.

[Vova585]

It is hard to suggest anything based on your description. Any intermittent problem is a nightmare. I would start with obtaining a capable scanner tool, if you are tech savvy get yourself a vida clone and have it next to you. Scan the car and see if you have any history codes that can help you at least to possibly narrow the issues to a degree. But if the problem is electric in nature(you mentioned that it is sudden, dashboard is turning off...) thats sounds expensive. I cant explain why the issue is only present with 85F and above(maybe some module is malfunctioning during high heat, but same should be true for when the car is being driven for a long time..I heard of more start problems with cold weather..).

[jonesg]

I have a 2004 Volvo V70 with a 2.5t engine. It has 276,000 miles and has developed a recent problem, While driving the engine acts as though it misses a beat, but actually acts as if all electrical power shuts off and then immediately comes on. This only happens when the outside temperature is above 85 degrees Fahrenheit, Sometimes it shuts down the dashboard and the car struggles to accelerate and I have no window or electric locks.
I disconnect the battery and the dash and accessories begin to work again.
What should I be looking at to correct this situation?

Bob
2004 Volvo V70 2.5T

in the engine bay, the fuse box, check fuse #8, its the computer ebox cooling fan.
If that fuse blows the ecm will throw hissy fits.

[abscate]

The 2004 had an issue with water invading the CEM and a TSB to fix that. Check to see if there is staining or water present

[leftyref56]

I will ask the next question: where would I find the CEM.
Another piece of information: The triangle in the middle of the dash board is yellow.
I will check the items mentioned and report back.
Thank you all for your help!
I have owned Volvos for the past 15 years and especially love this one.
Bob

[jonesg]

the fuse I mentioned is a hell of a lot easier to check than the CEM.
Considering it sat for a while, see if theres a mousey nest in the computer box.

[leftyref56]

I checked the fuse. It is fine.
I have found information that the problem is the CEM getting too hot. I don't always use the a/c. I am for now with it directed to the floor.

Has anyone had a good experience with these companies that repair the module or do I bite the bullet and go new?
Thanks,
Bob

[jonesg]

xemodex is the gold plated standard, there are cheaper options,

heres one in Naples NY.
https://www.g7computers.com/?gad_source ... X8EALw_wcB

[scot850]

Finding a good used CEM and having Xemodex check it and clone yours is another option.

Neil