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Juan Crespo
Juan Crespo, ASE Certified Technician
Category: VW
Satisfied Customers: 1523
Experience:  A.S.E. Master Technician, Advanced Level, Emissions - Asian, Domestic, & European
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02 Jetta 1.8t AWP auto, no start due to no spark. The code

Customer Question

02 Jetta 1.8t AWP auto, no start due to no spark. The code is for the ckp sensor no signal. I bought a new one due to removing it it looked pretty rough meaning magnetic tip was almost gone. However testing the connector I kept getting random ohm readings on pins 1-3 and 1-2 was slightly over ohm load of max 1.5 allowable 2-3 kept giving random ohms sometimes 50 then 70 then 2.5, one day i had the shop up to 75* and was testing the connector again same result I held the back of the connector tight then out of no where it started climbing and held @ 400 half of needed ohms (730 - 1000) as my friend and i sat there and just left it plugged in it went from 4xx to 8xx and mostly hovered around 730 dipping in that range 5 times in an hr with each dip taking about 20 25 mintues to complete.
So I thought problem solved the connector, I cut the connector off found the correct pins in the ECU, 82, and 90 tapped into those and ran new wire went to test and now I can not get more than 1.5 ohm even removing splice and putting ohm meter directly into the back of connector same reading. Fuses are all good check several times swapped relay 428 and 100 under the hood to check i'm lost on where to go from here please help. Thank you
Submitted: 1 year ago.
Category: VW
Expert:  Juan Crespo replied 1 year ago.

Hi there. Welcome to our site!

I can probably help you, but first I'd need to know what that code number was.

Best Regards.

Customer: replied 1 year ago.
it's PO322, only code I have and it's for the Engine Speed sensor. I just tested and have voltage @ relay 428 only about 11 volts. I can clear it and it comes right back. Also it doesn't see rpms and the tach doesn't jump or move as usual.
Expert:  Juan Crespo replied 1 year ago.

I'm sorry, but I need you to refresh my memory; what and where is relay 428? Also, do you have access to a graphing voltmeter or, better yet, a digital storage scope?

Customer: replied 1 year ago.
I do have a multi meter and genisys but only global for vw, i dont have euro unlocked unfortunately and dont have VAG. The 428 relay is under the hood, i found a forum post about bad ground so i just tried that and it did actually click the relay couple times and actually turned the epc light off however must have blown a fuse because now neither the fuel pump 100 relay are letting the pump turn on or the 428 relay is supposed to be for ECM power supply, would kind of make since i have power there but not to the ecu. As i said though i am chasing my tail and someone more qualified i believe is going to be much more help here than me chasing down forums as i have done for about 1 1/2 wks now.
Expert:  Juan Crespo replied 1 year ago.

If it's any consolation, this is a paysite and not a forum. All of us experts have been verified as such.

Back to the issue; are you talking about the Power Supply Relay that feeds the positive side of the ignition coils - should be by the brake fluid reservoir and have 5 wires connected to it? If so, check and see if fuse 29 (15A) in the fuse panel is OK.

This issue with the relay should have nothing to do with code P0322, unless the reference signal to the sensor has been lost. Can you check and see it there is any voltage at the Brown and White wires going to the engine speed sensor - try it with ignition on and with engine cranking.

Please let me know what you find.

Best Regards.

Customer: replied 1 year ago.
it's a huge consolation and why i decided to try this route :) your correct, obviously lol The relay i'm talking about is that one that's by the brake res.I had the signal drop before messing with that relay i just decided to test it due to posts i read.Symptoms from beginning. I would drive along and car would just shut off, then randomly restart also EPC light would come on intermittently and then also cause high idle of 1100 to 1200 then randomly seem to reset itself and go back to normal no light no high idle no random shut off. One day coming out of work it wouldn't start at all after 20 min of trying got it to start got it home and no start since then. Only code was lost signal of crank senser I was able to ohm test it got the results as i previously stated from the brown and white wire very very low ohms several times then randomly 400 for about ten minutes i moved the wires on back of ckp connector and it took of going up, to the point of running range of 8xx. But it would dip over a 20 min period down to 4xx ohms and raise again over 20 min hovering around 730 most of the "higher" range change. Next morning went out all i did was shut the multimeter off night before, turned it on and only 1.5 ohm!? So figured connector pin out cut the wires made them bare and same ohms, stuck the multimeter into the pinout on ecu Brown and White wire same ohms 1.1 to 1.5 testing pinout to ckp i do have continuity? I will go check the fuses to see if i blew one by grounding that now.
Customer: replied 1 year ago.
Fuse 29 is good but no power, using a test light. It does light up on other fuses so power is off to that fuse now which it was on last i checked them.
Customer: replied 1 year ago.
pulled fuel relay it now has power..... such a headache.
Customer: replied 1 year ago.
sorry relay 100 under hood near brake res.
Customer: replied 1 year ago.
it did blow a fuse when i grounded that it was fuse 37, it's replaced and EPC light is back on. I dont believe I am hearing the fuel pump could of swore it was kicking on before.
Expert:  Juan Crespo replied 1 year ago.

OK. I still can't remember or even find any reference to a "relay 100", so let's assume it is the Power supply relay which is fed by fuse 29, which also feeds the ECU/PCM. If fuse 29 has no power, that could mean fusible link 176 (110 A) next to the battery is blown. Look at the graphic I've attached and let me know.

After all of that, can we get back to checking voltages at the Brown and White wires going to the engine speed sensor? - try it with ignition on and with engine cranking.

Please let me know the results.

Expert:  Juan Crespo replied 1 year ago.

Hey. I just remembered something from years back that use to drive us techs crazy: the grounds under the battery tray (see attached pic.). Make sure to take the time to remove the battery and the tray to clean and redo the three grounds under there - trust me on this one; you won't regret it.

Best Regards.

Customer: replied 1 year ago.
I'll have to check the Fuse link 176 when i get home, and I did remove the battery and recheck the grounds under the battery. I had heard there were some under the tray so I removed the bolt and cleaned with batt. terminal cleaner wiped clean and reinstalled all. Didn't change anything. For the brown and white wire switching to volts, memory serves correct it's .5 volts key off key on only went up to .8 and cranking i wont say a number but i know it didn't change much. I will get you a 100% after I get off work but as i said i know it didn't change much if any.
Customer: replied 1 year ago.
My relays are flipped this is what I have for relay 100 which is for secondary pump inj. I have found some flipped some that way my wires support mine being flipped. The wires under are label 428 and 100 on power wires. Also after replacing the fuse 37 fuel pump kicks on but doesn't prime every time.
Expert:  Juan Crespo replied 1 year ago.

Going by the pic you uploaded, the relay marked 100 is the power supply relay, which we techs know as J271- that's the one that gets is power from fuse 29. The one marked 428 (J299) is just to power the air pump when the engine is cold. fuse 37 (10A) just supplies ignition voltage to the cluster and the radio.

Regarding testing crank sensor circuits, the repair manual tells you to check resistances. Problem with that is that even if the resistances are found to be OK, you don't get to see the actual signal; that's why I recommend using a cheap pc-based scope (less than $100 online) to make sure the engine speed signal is in fact getting to the ECU. Once we know that signal is OK and getting to where it needs to go, we can look at other ECU outputs to see how it is reacting.

Good job on being proactive in taking care of those pesky grounds under the battery!

Customer: replied 1 year ago.
Thanks, ***** ***** nip this issue in the rear. Unfortunately I don't have the $ to buy osci. scope I do understand what your saying though about signal making it to the ecu. I tried borrowing one from a friend but he's been less then so options are limited right now. Is there any other way I can see? I have tried switching ecu's out and that didn't work either
Expert:  Juan Crespo replied 1 year ago.

The reason I said to use a scope is because the readings you took with the Ohmmeter were all over the place. Could you at least see if you can get actual current voltages at the White and the Brown wires to the crank sensor?

Customer: replied 1 year ago.
I only get around .5v and 1.1V as stated at most. I was fairly certain I had a voltage drop I was just hoping to narrow down that it was the crank connector wires or figure out where exactly the entire circuit ran for the CKP sensor. After seeing this previous kids wiring coupled with ohms and volts having at most of any given time in the beginning before it lost almost all it only 5 volts at the brown and white. I think I'm going to replace the two main harness's and coil pack harness since it has cracks. When I have 12.8 to little over 13 volts at the battery I don't get the full voltage by the time it hits the relays 428 and 100 right there by the brake booster. So instead of compounding multiple issues, bad wiring, poor wires and by now it could have fried the circuit and i'm going to replace the fuse box as well. I would love to repin but not going to risk catching the car on fire if a wire does end up taking too much load and frying the wire/coating also speaking of unrelated wires to the issue unfortunately.
Expert:  Juan Crespo replied 1 year ago.

Sounds lik you have a good plan. Please let me know if assistance is needed.

Best Regards.