'01 V70 T5 nostart stall ECU /connection ..clone solved Topic is solved

[draser]

Tach signal I believe is generated by the crank sensor, then there's some conditioning circuitry. Can you check wiring/connector for the crank sensor?

[ac134]

Hi draser,
Sorry for the late reply. I will check the crank sensor wiring and connector. I appreciate the help.
Thanks, ac134

[ac134]

UPDATE: Finally fixed my 'no start' issue by replacing the ECU with a cloned eBay ECU.

I was able to narrow down the source of my 'no start' issue inside the engine bay by the ECU or ECU connection. I was able to start the car after a a long crank (30+ secs.), I then tapped/jerked the ECU which caused the engine to stall. I was was able to recreate the engine stall twice consistently but still unsure whether it was the ECU are a loose connection. I decided to purchase an eBay ECU with the same exact part number. I then sent my original ECU and the eBay ECU ARD Tuning to have them cloned. After a few days I got back my original and cloned ECU's from ARD. I installed the cloned ECU and started the car with one click. I've been using the V70 for a week now without any starting issues.

Thanks to all who assisted in troubleshooting this intermittent 'no start' issue. ac134

[abscate]

Thanks for the follow up ! The tapping is almost certainly indicative of a bad connection. Did you try removing and reseating the ECU?

[ac134]

Yes, I tried re-seating the ECU multiple times but the 'no start' symptoms persisted. That's the reason I decided to replace the ECU.

[ac134]

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[Mojobaby27]

Thanks to DGM for his input on the PNP switch, I was having this problem for about two weeks, The tachometer would bounce Up n down or stay at the Max and the car would have trouble starting. So I took aluminum tape and insulated the power wire going to the starter, but that did not help. So I tried DGMs suggestion of moving the shift lever from park to low about 10 times and it seems to have made it better, for three days now I haven't had the problem. As others have said it happened only after sitting for a while, it started when it was warm any subsequent restart so no problem for that day.

[oragex]

One thing to check about the ECU (modules located just in front of the power steering fluid reservoir) is the small fan located inside the rear hose going from the ECU housing. This is just a regular fan that gets slower and may stuck after 10 years. It will cause the ECU modules to overheat and fail.