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Discussion Starter #1
2001 New Beetle 2.0L Cranks but wont start or even act like its trying. Can not hear fuel pump prime up. The theft light in the cluster comes on with all the rest when key is turned on and goes off with the rest when cranking and stays off from then on. I don't smell gas after prolonged crankng as I might expect if the pump was working and it was a no/weak sprark problem.

Ran codes and got the following:

P0725
P1780
P1850
P0725
P1780
P1850

Cleared the codes and cranked it agian and got the following:

P0725
P0303
P0301
P1780

Cleared again and cranked, got the following:

P0725
P0303
P0201
P1780

Then after clearing again (each time I clear them it says codes cleared) I did not crank the engine but left the key on and rechecked for codes and without doing anything at all and there were code still or again depending how you look at it. I got the following:

P0725
P1780
P1850

The only thing I feel sure of is that I do not need to send it to the dealer to have the key and computer remarried. My best guess is that it needs a fuel pump or realy, an ecm, or some other electrical fix but I do not know where to start as I have never had much call to work on VW anything at my shop and I have never been strong at electrical in the first place. I have been out of the biz for a couple years now but still have my old shop and most of my tools but feel a little lost on this one. Better still it's the wife's car and she thinks I can fix ANYTHING easy as pie!

As a side note someone had bumped her in a parking lot and creased the passenger door an into the quarter panel. We had it repaired and the body shop replaced her door with a used and fixed the quarter. The car ran fine when we got it back but after a few days of use she went out to go to work in the morning and it was a no start. It was below zero cold so I tought maybe she had a frozen fuel line or the like and I towed it to my shop to thawed it out but but still no start.

That’s where I stand now.

Thanks
 

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The P0725 code is for an open or shorted engine speed (rpm) sensor. Without this sensor the fuel injectors will not operate so this is likely to be the cause of the no-start. With this code it could be the sensor or a fault in the wiring. The sensor is located on the front of the engine near the oil filter. It has 3 wires coming from it and is held in by a single bolt.

The resistance specifications for the sensor are:

Pin 2&3 480-1000 ohms
Pin 1&2 open
Pin 1&3 open

Pin 1 is at the square end of the connector.
 

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$3 can of starting fluid will give you an idea if the engine will at least fire off, if it does it is likely the fuel pump.

You could pop the rear seat and access cover and try to bank on the top of the tank, fuel sender to see if you can jar the pump into working again, but be careful and do not think this will get you much further with the car.

Crank sensor code may be a red herring but could also be an issue.

If the crank sensor is the issue, starting fluid will have no impact.
 

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Can not hear fuel pump prime up.
The fuel pump should prime when the driver's door is opened. It will only prime if the pressure in the line has dropped sufficiently. Once the fuel pump has primed one time it can take 1/2 hour for the line pressure to drop to the point where the pump will prime once more.
 

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Discussion Starter #6
I had tried starting fluid first off and it did nothing whatsoever so that tells me no spark. Also there is no sound from the pump and no smell of gas after extended cranking so no fuel. I will check the pump as it sounds easy to do but don't think it's the problem. I will get under it and see about sensor and wiring/connection.

Just to keep things up to date, today I went through the fuse panel and found nothing blown. I noted what each fuse did with the key off, key on, and key cranked and attached it to this post in hope that it might be of some help as well. Thanks

Color Code as follows:

Green = Live with key off
Red = Dead always
Yellow = Live Key on - off when cranked

 

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I'm not sure about that. I think the ignition system works just fine without the crank sensor. It is only needed for the fuel injection.
Crank sensor is the primary sensor for ignition, this along with the cam sensor is required for the fuel injectors.
 

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Check relay 4 fuel pump relay (it's numbered 409)easiest check is to borrow a known good from a fellow bug
Edit_2013-02-13_1.JPG

Fuse 28 Third from the bottom of your picture 15 amp should be live all the time most certainly with key on. Power flows through relay to fuse 29 then to fuel pump.
Edit_2013-02-13_2.JPG

Edit_2013-02-13_3.JPG

Edit_2013-02-13_4.JPG
 

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Had the exact same symptom and code and on my 2000.
Replaced the seonsor in the school parking lot where it failed.
New one came with a new o-ring (think it was $45?)
Just one bolt that required a wobble extension to the get the right angle.
Kind of tight for my huge hands, but it only took 10 minutes.
 

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Discussion Starter #10
crank sensor

I pulled the sensor to check the pins. Not sure I'm doing it correctly but I set my cheap meter (as I said I'm super weak at electrical) and set it to 2000k ohms and probed pin 2 & 3 and got a value of 001 and then set it at 200k and checked it again and got 00.9 the 1&2 and 1&3 did not make the meter change at all so I'm guessing that wound be open? So I think you may be right in that the sensor is no good because of the pin 2&3 reading being off. Unless I tested it wrong.

Please advise

Would that being bad cause the 15 camp fuse at 28 on the dash fuse panel (fuel pump (FP) ) to be dead all the time as I showed it the fuse panel picture?

I would just throw a new one on it but they want 110 dollars for it at my parts store and as you know they are now returnable. Where are the 45 dollar ones ppl are talking about?

Thanks
 

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ohms of sensor

I pulled the sensor to check the pins. Not sure I'm doing it correctly but I set my cheap meter (as I said I'm super weak at electrical) and set it to 2000k ohms and probed pin 2 & 3 and got a value of 001 and then set it at 200k and checked it again and got 00.9 the 1&2 and 1&3 did not make the meter change at all so I'm guessing that wound be open? So I think you may be right in that the sensor is no good because of the pin 2&3 reading being off. Unless I tested it wrong.

Please advise

Would that being bad cause the 15 camp fuse at 28 on the dash fuse panel (fuel pump (FP) ) to be dead all the time as I showed it the fuse panel picture?

I would just throw a new one on it but they want 110 dollars for it at my parts store and as you know they are now returnable. Where are the 45 dollar ones ppl are talking about?

Thanks
Can your meter go to a lower scale to make it easier on you? seems like you did measure it correct and you got 900 ohms according to what red99 said on pins 2&3. Good luck in replacing that sensor.
 

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Discussion Starter #12
Recheck

OK I set it down at 2000 (I did not see that I could go lower) and the reading came back 889 so that would mean the sensor is fine correct?

Thanks
 

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I pulled the sensor to check the pins. Not sure I'm doing it correctly but I set my cheap meter (as I said I'm super weak at electrical) and set it to 2000k ohms and probed pin 2 & 3 and got a value of 001 and then set it at 200k and checked it again and got 00.9 the 1&2 and 1&3 did not make the meter change at all so I'm guessing that wound be open? So I think you may be right in that the sensor is no good because of the pin 2&3 reading being off. Unless I tested it wrong.
The best scale to use would be "2000." This means that a full scale reading would be 2000 ohms. You should read between 480 and 1000, so roughly between 1/4 and 1/2 full scale. "Open" means the reading should be infinity, or no movement of the meter so the 1&2 and 1&3 readings are good.
 

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OK I set it down at 2000 (I did not see that I could go lower) and the reading came back 889 so that would mean the sensor is fine correct?
Yes, that is the correct reading. The problem could still be in the wiring. Check the wires from the sensor back into the harness and the harness to where it connects to the body for any signs of damage.
 

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Discussion Starter #15
I checked it at 2000 and it came back 889 so I'm saying the sensor is good. I'm not sure where to go next on this, relay maybe? I'm not sure where they are tho. I'm tempted to feed that fuel pump fuse 12 volts and see if it runs but don't want to make things worse.

Contemplating next move please advise.
 

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Would that being bad cause the 15 camp fuse at 28 on the dash fuse panel (fuel pump (FP) ) to be dead all the time as I showed it the fuse panel picture?
The fuses should have power on the left connector as this is the side that runs to the battery. The right side goes to the load so should not show voltage with the fuse removed.

The power for fuse 28 comes through the fuel pump relay (#4) shown in the diagram someone posted earlier. Before the relay it comes thorough one of the fuses in the panel on the top of the battery case, so take a look at that panel. I believe the relay panel is above the driver's side kick shield above the pedals. You'll have to remove that panel. There are 3 screws on the edge and then it slides toward the rear of the vehicle.
 

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Also, I just noticed that all the other fuses that you show as "dead" are powered through the fuel pump relay as well.
 

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Discussion Starter #18
Turns out the Pump DOSE cycle

The wires look fine and when I checked the black wire at pin 1 on the car side of things it showed to be a good ground key on and key off. The brown and the white wires showed neighter ground nor hot with the key off or on.


Also after seeing people say the fuel pump cycles when you open the drivers door I listened for it again and I was surprised to hear that it did in fact cycle! Now I'm even more confused. The sensor is still out of the car and the fuel pump fuse is still dead. I don't know if it flashes on while the pump cycles as there was way to get to it before it stopped after I open the door. I could run an extention wire from it and check it that way but I will have to wait for a half hour or so for the line perssure to drop off so that the pump will cycle again.
 

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Discussion Starter #19 (Edited)
So it looks like its time to after the relay next. I could just go grab one of them as they are around 14 dollars but if there is a way to test it I would like to do that.

All the lines (5) and fuses (3) on top of the battery are good and have power.

Side note: Why is there a black wire (far left) on the top of the battery that has power with the rest of the wires that are red (3) and one red with black stripe? I know its ok as they are connected to one another but man it just looks wrong and I got enough trouble as it is! HaHa


Anyway......Thanks again for sticking with me on this one.
 

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After further deliberation, the fuel pump relay is controlled by the ECU. The ECU may be programmed to only close the fuel pump relay when the RPM sensor shows a nonzero value (other than the brief time as the door is opened). So it is possible that the engine speed (RPM) sensor is still at the root of the trouble.

Your car is old enough that you might consider replacing the engine speed sensor as part of preventative maintenance anyway. They do fail relatively often and generally cause sudden engine stalling, so can be dangerous. I plan to replace mine at my next oil change as preventative maintenance. I have had one incident that I strongly suspect was the engine speed sensor. I was on a highway going about 60 mph when the engine just completely cut out. No unusual noise or vibration or anything, just total loss of power. About 2 seconds later the engine came back on, again no noise or vibration, just completely back to normal. Since I have a manual transmission the car's momentum carried it through no problem. People with automatics can have the engine stall.
 
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