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Discussion Starter #1
So my sons car will not start, just turns over. Here's the list of what i have done..

Battery is good
checked fuses
fuel pump is running
getting fuel to the engine
pulled connector from plug boot and with key to on i have only 1.6 volts
tried a new crankshaft position sensor. still no start or power to the coils
wasn't throwing a check engine light before it stopped

Any input would be great....Thanks
 

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Discussion Starter #2
Well even though theres been no response..
I replaced the relay next to the ecm and not I have 12 volts at the pool for the coils but no spark..
 

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Engine code might be helpful (ATW or AWM).

With key on, check for power at fuses 29 and 34; you should have 12V.

A quick test for crankshaft position sensor (aka engine speed sensor, ESS) is: crank for at least 5 seconds continuously. After 5 seconds, the ECM ignores the missing ESS sensor and fires the injectors and plugs anyway (a limp mode). In normal cranking, there's no spark or fuel injectors until the ECM sees an ESS signal.

The common power wire to the coil packs is red/green, and it's powered from the relay you changed. The ECM switches the negative side of the coil packs (and nearly everything else). It's counterintuitive, so don't let it trip you up.

However, you'll get a code for almost everything (with a few exceptions to make you crazy), so start with the above, easy checks.
 

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Discussion Starter #6
I only have 1.6 volts at fuse number 34 and 12 volts at fuse number 29..
The engine code is atw and I did try a new crank shaft Sensor with no luck. If I don't get it going it's going to a salvage yard..
 

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Fuse 34 is powered from the fuel pump relay, but it's not energized with just the key on (i.e. engine not running).

Fuse 32 is powered from the ignition switch; I missed it in the schematic yesterday, so please check it.

Fuse 32 powers the fuel injectors, so it's obviously critical (black/blue wire). If you don't have power at fuse 32 with the key on, the ignition switch is your culprit, as Emry astutely suggested. The ignition switch is a relatively common failure point in these cars.

Also noteworthy, the wire from the ignition switch to Fuse 32 also powers the fuel pump relay coil, so without power from the ignition switch to Fuse 32, Fuse 34 will never have power. (The ECM switches the negative side of the fuel pump relay and the injectors.)

Ref. Bentley schematic 37.
 

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I've got 3.4 volts at fuse 32 with the key turned on.....
That's 8 or 9 volts too few...

The ignition switch isn't bad to install; your son should be back on the road soon.

If you want to double-double check, fuse 31 (back up light) is fed from the same terminal (15) on the ignition switch.
 

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Discussion Starter #10
Well tried a new switch and nothing, still no power to fuse 32. Think I'm going to try and trace the wire
 

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Referring to Bentley schematics 35 and 37:

The wire is black (no stripe).
It begins at Ignition Switch terminal 15 as 4 mm[SUP]2[/SUP] (10 AWG).

It is spliced in the instrument panel wiring harness to:
  • 2.5 mm[SUP]2[/SUP] (12 AWG) wire to Fuses 31 & 5
  • 2.5 mm[SUP]2[/SUP] wire to Fuse 32
  • 2.5 mm[SUP]2[/SUP] wire to fuse7
  • 0.5 mm[SUP]2[/SUP] (20 AWG) wire to Fuel Pump Relay socket pin 15/19 (+ side of coil) on relay panel
  • 0.35 mm[SUP]2[/SUP] (22 AWG) wire to Instrument Cluster 32-position connector pin 15
  • ...and maybe some other places
I hope that leads you to the fault--the splice is certainly suspect. I believe the fuse panel will readily come out; that might give you decent access.

If the fault is in the splice, a Wago 221-415 or two would be just the ticket. Or maybe a split-bolt (electrical aisle at Home Depot, etc).
 

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Discussion Starter #12
I have power from the ignition switch to the fuse block but it does not jump power to fuse 32. So I did a quick jumper and had power to the injectors and still would not start.. Think time for the salvage yard
 

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So my sons car will not start, just turns over. Here's the list of what i have done..

Battery is good
checked fuses
fuel pump is running
getting fuel to the engine
pulled connector from plug boot and with key to on i have only 1.6 volts
tried a new crankshaft position sensor. still no start or power to the coils
wasn't throwing a check engine light before it stopped

Any input would be great....Thanks
Was anything done to the Passat before it would not start?
Someone just had a non-start issue with their 2000 Passat and discovered that a NEW mirror switch was blowing a fuse preventing the engine from starting.
So the engine was running and stalled/died while driving the Passat?

OK what do you mean the fuel pump is running? It should only run when its relay activates it. Also that FP relay might power more components?

Did you double check all of the connections to the battery so they are clean and tight?
Ground wire by #1 spark plug clean and tight?
You have replaced the ECM relay located under the hood in the ECM box and checked ALL fuses in the different fuse boxes? I use a 12 volt probe to check for fuse power.
You have temporarily installed a new ignition switch and still no start? Do the power windows function?
Do the dash lights come on and the tach move when you crank over the engine?
 

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Discussion Starter #14
Clean battery post, new relay for ECM, I can hear the pump prime when I turn the ignition to on, windows - lights work ground is right. Tach does not move when trying to start and checked all fusses.
 

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You said you have tried a new speed sensor. Have you checked whether it's properly installed and connected?
 

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Tracing back the wires from the fuses to their source is a good option at this time. You need to find out why the required voltage is not present at the fuse. Either the wire is cut or it's disconnected at its source.
 

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Discussion Starter #18
Thanks for the help everyone.

Still wasn't able to get it going and I have three other projects that I need to get done..
 

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Not sure if this helps, but.... My other vehicle (ford) had an issue similar that ended up being the neutral safety switch. It would turn over but not spark due to the vehicle not thinking it was in park. A possible test it to try to start it in Neutral (if automatic). Not sure if the VWs have a similar mechanism. Also, while attempting THAT fix, I was told that there are possible Anti-Theft measures that have to do with the key chip not properly reading in the ignition cylinder. But then again... this was my ford.
 
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