Error code P0601 internal control module memory check sum er

cheese31378

Hi guys i have a 51plate Vectra 2.2 sri and i am having some problems that i can't figure out.
I have had this fault for nearly a year now 10000 miles
Error code P0601 internal control module memory check sum error.

when i start the car from cold the engine starts racing it revs at 2500 and stays there for about 15 secs drops and starts fluctuating between 400 and 800 revs.
it seems to try and cut out then revs itself up then goes to cut out then revs itself up again and continues to do this untill i switch the engine off and back on depending how warm the ambient temp outside is.
the emissions light and traction light are lit up too.
No power to drive car either.
The fault is in the dash when i turn the key before i even start the car.
If I leave the car overnight and the next day leave the car in the sun before i start it. it is fine.

i have cleaned the throttle body and egr and had the plugs changed and the coil pack replaced and all seems to be fine.
Car runs fine all day. it only happens when left for more than 10 hours. less in winter.

I have just come back from a 1500 mile trip to France and the car ran fine no probs at all 42mpg!! but the fault is still there when left overnight.
It is definitly temp related but can only try to mend it for a short period in mornings. as the car is fine all day.

any help would be much apreciated as i am really stuck.

jbaggaley

Cts ? Also is car reading outside temp on dash ?

cheese31378

Re: Error code P0601 internal control module memory check su

Thanks for your reply jbaggaley
I have removed the coolant temp sensor when left over night so fault is there then and warmed the sensor up with heat gun. turned ignition on fault still there as normal and temp gauge went sky high as sensor was warm. as for the outside temp that also seems to read normal. 17 degrees today lol

can you think of anything else i could heat up to see it it cancels the fault out?

also tried removing some conectors and gave a squirt of wd40
the one behind battery thats round, the two on the ECU the one conected to the tc/abs unit. also bench tested EGR valve and that seems ok.

Its hard for a garage to find the fault as they need it overnight and got only a matter of seconds/minutes the find fault. and anything they try I will have to wait till next day to see if it works.

I have owned the car from 8 months old 13000 miles and apart from this fault its A1 no rust or minor dents. engine replaced at 24000 as timing chain failed. so this engine has only done 55000 miles replaced under warranty.

As soon as a bit of warm gets to the fault its gone. pluged a tech 2 in and got p0601 that clears until next morning. engine fires up first time every time even when it was minus 17 last winter. (when the fault was there). the accelerator pedal does very little under the fault condition i forgot to mention as well if that helps towards finding out whats wrong.

last winter when it was so cold it took about 5 mins to get right every morning. as for now we nearly in summer it takes about 30 seconds.

Thanks again.

jbaggaley

Is it cable throttle or fly by link if fly by link could be throttle control module on tb

jbaggaley

Failing that ecu fault

cheese31378

Re: Error code P0601 internal control module memory check su

its fly by link mate.

jbaggaley

First try that I would say

cheese31378

Re: Error code P0601 internal control module memory check su

Car got worse and worse it was doing the fault after just a few hours of being left, so had to really look into it further. so i decided to look for a new ecu. and thanks to you guys on this site i realised i needed my transponder and chip programmed to the new ecu so i looked on Ebay for all three and found someone.
Car is now sorted!!
Brought a second hand ecu, transponder and chip for 28 quid delivered!! from whipstreetmotors on Ebay.
Took 40 mins to fit and car now runs as it should and there was no need to plug car into computer. it really was plug and and play.
alarm central locking all works as it should too.
Well happy. 😃

MikeS

Re: Error code P0601 internal control module memory check su

🙂