Technical ECU virgin

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Technical ECU virgin

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Sep 30, 2013
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Hi All,

I'm chasing a P1221 fault on my Panda Dualogic. I purchased the car in December 2019 and it was working great until a week ago when the MIL flashed up.

Anyway, I've confirmed that it is the electronic pedal and it did have severe corrosion on the terminals but I swapped the terminals around and I still have the same code, so I may need a new ECU. The cable harness bells out OK. It seems like the previous owner(s) have played around with cables and connectors and opened up the ECU.
So if I purchase a virgin ECU do I need to take it to a dealer to make aligned with the body computer?

Thanks.
 
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I don't want to confuse matters but before you install the new ECU it might be worth checking the Throttle Position mounted on the throttle body.

The P1221 code is very ambitious. A believe its a correlation error.

In some cars there's two sensors in the throttle body and if they read different it throws up an error.


As we see in the Panda the error being fixed either by a throttle body or throttle peddle I suspect both could cause this error be thrown up.

if you have some way of logging live data its an easy check an Worth doing as the ECU has more resale value before its been coded
 
Thanks.

I have an OBD connector on order.
The pedal potentiometer connector pins were very badly corroded and they have been cleaned with nail varnish remover! But the potentiometer itself shows some pin corrosion so a secondhand one has been ordered.
Fault is intermittent. I've taken some readings off the potentiometer and not sure if they are correct (readings in ohms) -
A - B 1684 released 1684 pressed
A - C 1140 released 1766 pressed
B - C 1138 released 1771 pressed

D - E 1084 released 1084 pressed
D - F 1917 released 1098 pressed
E - F 1162 released 1948 pressed

I didn't expect the signal readings to be reversed
 

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Looks like there are two potentiometers within the pedal

sensor 1
A and B are ground and 5V
c signal

sensor 2
D and E are ground and 5V
F signal

depending on whether you put the First probe on the signal or ground the results will be reversed


usually. it will just be a dead part of the track causing a glitch when the pedal is pressed slowly. Looking on a graph should show a smooth progression
 
Agree.
My understanding is with the accelerator fully pressed is @5v signal on C and F.
F does suggest decreasing resistance therefore increasing voltage but C is the opposite.
Anyway, it needs diagnostic analysis to proper determine.
Thanks.
 
Received the replacement secondhand pedal and swapped over and now OK.
Resistance readings of the replacement pedal were -
AB 1753 / 1753
AC 2614 / 1961
BC 1130 / 1792

DE 1090 / 1090
DF 1885 / 1089
EF 1129 / 1946

D-F similar to the old pedal
A-C now decreases when pressed

I wasted a day by following a red herring; the previous custodian took the wiring loom, ECU connectors and ECU apart when they should have looked at the most obvious component - the pedal.
 
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