How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask AudiDoc Your Own Question
AudiDoc
AudiDoc, Independent Audi Shop Owner
Category: Audi
Satisfied Customers: 1695
Experience:  I've been working on Audis since I was 18 and own an independent Audi repair and performance shop
14582033
Type Your Audi Question Here...
AudiDoc is online now
A new question is answered every 9 seconds

What causes esp,ecp and parking brake fault lights. Car

Customer Question

what causes esp,ecp and parking brake fault lights. Car hesitates to start and shakes when idling. P2294 and 129B codes
Submitted: 1 year ago.
Category: Audi
Expert:  Wolfgang replied 1 year ago.

Thanks for choosing Just Answer . I'm Wolfgang here to help!!

I am confident we can resolve your problem together. Please
understand that I don't know your skill level. In most cases when you have a problem
with the way the vehicle performs, specialized tooling is required to acquire computer
data/information or engine testing results. We didn’t build these complicated vehicles; we
just diagnose and fix them. Also understand that I can't see, smell, hear, or touch the
vehicle either, so it may take a few replies to get to satisfactory results. I am also going to
direct you with the fastest, easiest and most common things to check first. Please be
patient and permit me to do what I do best.
I also try to give all of the information you may need, expecting a “positive rating” in
return. I will also continue assisting you after you have rated me, if necessary. If there
is any reason I cannot get a positive rating, please let me know why “in advance”, so I
can go another direction for you. I am sorry you’re having this problem; I’ll help you
through it.
Below is my first answer or request for more information. If you do not understand it, or you need more information from me, or need me to go in more detail.

ok the fault we need to really focus is the p2294 fault. which is the mechanical fuel pump regulator valve has an open circuit.

make sure first that both pumps are pluggen in and there are no broken wires in that part of the wiring near the pumps.

now i see you did replace the pumps .... why same codes , different codes ? can you explain!

do you have VAG COM scan tool?

i do need a vin #

thanks

Customer: replied 1 year ago.
VIN # WAURV78T29A051696. I don't have VAG COM, I used Innova 3120 to scans for codes. Codes are the same as before changing right fuel pump, P2294,P129B,P2257,P0458,P0100,P2401,P2006,P2007. Before changing left fuel pump the vehicle was stalling and practically un-drivable. After changing it performance improved but engine seemed to be producing whining sound when idling. After changing the 2nd pump performance did not improve, car shakes on idle ,takes longer to start, after warming up seems to improve somewhat but occasionally seems to wanna to cut off in lower RPM but doesn't
Customer: replied 1 year ago.
Wiring appears to be intact. I am sure not if there are separate fuses for fuel pressure regulator. Only P2294 and P129B appear to relate to problem and both relate to fuel pressure regulator bank 2. Also, codes re-appear almost immediately after erasing, disconnecting the battery does not seem to change anything. ESP,ECP and parking brake fault lights are on along with beeping sound on start-up
Expert:  Wolfgang replied 1 year ago.

ok let me do some digging on this and will be back later . i will have a plan of how to tackle this . Vag com may be needed to get some measured reading while running!!! FYI

Customer: replied 1 year ago.
Just wondering if you've made any progress with my problem?
Expert:  Wolfgang replied 1 year ago.

i need you to look at the connector station under the ecu drivers side red connector . is there any corrosion or the terminals oxidized?

Customer: replied 1 year ago.
What is the specific location in the vehicle?
Customer: replied 1 year ago.
is it next to brake fluid reservoir?
Expert:  Wolfgang replied 1 year ago.

in the cowl area drivers side black cover box

Customer: replied 1 year ago.
Is this the box you were referring to?
Expert:  Wolfgang replied 1 year ago.

no the box is on the other side of the master cylinder

Customer: replied 1 year ago.
Ok, this is the master cylinder and windshield wash reservoir on the other side of it. I can't see anything else. Do I have to remove the black plastic piece from windshield wash reservoir in order to get to connector station? I just want to make sure before I start taking parts out.
Expert:  Wolfgang replied 1 year ago.

i need a vin # please

thanks

Customer: replied 1 year ago.
VIN # WAURV78T29A051696
Expert:  Wolfgang replied 1 year ago.

here is a pic of the ecu its under that where the red connector is at!!!

Customer: replied 1 year ago.
I got access to ecu. The red connector appears to be in perfect condition. I didn't inspect the ecu, not sure if I should take it out. I think you mentioned just the red connector before
Expert:  Wolfgang replied 1 year ago.

ok do you have a digital volt ohm meter?

Customer: replied 1 year ago.
No, but I'll get one. I'll let you know when I have it
Expert:  Wolfgang replied 1 year ago.

OK LET ME KNOW!!

Customer: replied 1 year ago.
ok, I got a hold of digital multimeter and ready to proceed
Expert:  Wolfgang replied 1 year ago.

ok key on engine off on the #2 fuel pump drivers side do yoi have battery voltage from pin one to ground with your meter?

Customer: replied 1 year ago.
I am not a master electrician, so my electrical experience is somewhat limited. If I understood correctly, I have to unplug the fuel pump and measure the voltage from the plug with ignition on but engine not running. There are 2 wires for each plug and I don't know for sure which one corresponds to pin 1. If I did it correctly, I get 2.68 for left and 2.47 for the other on both sides - driver and passenger
Expert:  Wolfgang replied 1 year ago.

on the drivers side pump if you look at the connector it is numbered and you put one lead of the meter in pin one of the connector and the other lead to battery negative . you should have what voltage?

Customer: replied 1 year ago.
I figured out the pins, I see where they are numbered 1 and 2. I have a question regarding my multimeter. The selector on it is different from the ones I've seen before. Which position should be in to get voltage measurement? Please see the enclosed pic
Expert:  Wolfgang replied 1 year ago.

turn to the right 1 click to dc v then measure

Customer: replied 1 year ago.
I got 2.65 and that's for both pumps, both give the same reading
Expert:  Wolfgang replied 1 year ago.

that is with the pump connectors disconnected correct?

Customer: replied 1 year ago.
that's on pin 1 on the connector with the ignition on engine off
Expert:  Wolfgang replied 1 year ago.

let me see the wiring diagram again !!! hang on

Expert:  Wolfgang replied 1 year ago.

pin one is red with a white tracer wire correct?

Customer: replied 1 year ago.
Correct
Expert:  Wolfgang replied 1 year ago.

ok that wire should have 12 volts . now we are getting somewhere!!.. that circuit affects other sensors too

please see pic .

under the ecu is a relay station . replace (A) relay and then recheck voltage at the same pin after new relay installed.

Expert:  Wolfgang replied 1 year ago.

do me one favor with the pump disconnected and car running are you still only getting 2 volts on that same wire

Customer: replied 1 year ago.
With engine running I got 12.4 when just started, then dropped to 11. checked both sides unplugging one at a time, same reading for both, around 11
Expert:  Wolfgang replied 1 year ago.

that is still low needs to be charging voltage so replace the "a" relay then recheck

Customer: replied 1 year ago.
could you specify which relay and location please?
Expert:  Wolfgang replied 1 year ago.

LOOK AT THE PIC I HAVE SENT OF THE RELAYS . REPLACE (A) RELAY ON THE LEFT

Customer: replied 1 year ago.
I got it. I missed that answer by accident but saw it later. Ordering the relay already. Thanks
Expert:  Wolfgang replied 1 year ago.

my pleasure!!

Customer: replied 1 year ago.
Hello! I got an update on the problem. I swapped the relay for the new one. In the picture the one with number 645 on top, it supposedly an updated part because the old one was 643 like the other 2 you could see. There was no improvement performance wise, still same lights on, uneven idle and shaking. With engine off, key on it reads about the same - 2.65v, with engine running however it can't seem to get a steady reading though. Originally it just constantly jumped between 17 and 25, then I shut the engine off and tried again. The second time voltage jumped between 7.6 and 7.9 but settled on any particular number n both instances. I also swapped relays around, I got another 643 from a different slot and switched it around with 645 but no difference.
Customer: replied 1 year ago.
Here are the pictures of the relay station
Customer: replied 1 year ago.
Correction on the previous, I meant to say I can't seem to get an exact reading with the engine running, just constantly changing numbers, never settles on a definite reading like it should. Unless I am doing something wrong
Customer: replied 1 year ago.
Customer: replied 1 year ago.