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VWDoc, Independent VW Shop owner
Category: VW
Satisfied Customers: 6457
Experience:  20 years of experience working with VW's. Independent European shop owner and technician.
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1999 Jetta: P1451, P1421, P1425, P1472, and P0102 wont go away

Customer Question

1999 Jetta 2.0 AEG. P1451, P1421, P1425, P1472, and P0102 won't go away. Voltage supply to MAF is only like 4.5 volts. Replace Fuel Pump Relay, tested continuity between MAF and relay and there was continuity to a couple wires. Car runs fine, just the codes immediately come back
Submitted: 5 years ago.
Category: VW
Expert:  VWDoc replied 5 years ago.

VWDoc :

Hello, I'm Jason. I will do my best to answer your question quickly and accurately using the information you have provided.

VWDoc :

ok, let me do a bit of code research first...

VWDoc :



Sec.Air Inj.Sys.Circ Short to Ground




Sec.Air Inj.Valve Circ Short to Ground



Tank Vent.Valve Short to Ground



EVAP Emission Contr.LDP Circ Short to Ground



Mass or Volume Air Flow Circ Low Input

VWDoc : do some wiring tracing....please be patient

VWDoc :

Ok, I know this sounds odd, but is fuse 43 intact and have 12v through it with the key on?

Customer: replied 5 years ago.
Ok let me know when you're ready.
Expert:  VWDoc replied 5 years ago.
Please check fuse 43 for integrity and power. Also, make sure all fuses on top of the battery are intact, primarily both 50A strip fuses
Customer: replied 5 years ago.
wow, too easy, fuse 43 was missing. can you tell me any reason why someone may have removed that fuse. Codes are gone now.
Expert:  VWDoc replied 5 years ago.
Bingo! No idea why it's gone, but glad this nailed it. Who knows, there may be some further check engine light issues once the readiness monitors start to run, but glad to hear we've gotten this far.
Customer: replied 5 years ago.
Ok, yeah the car also needs a cat, so I'll accept as soon as the car passes inspection just in case I need a little more help. Which will hopefully be by tomorrow. Is that ok?
Expert:  VWDoc replied 5 years ago.
no problem. Accept or not, you can always continue with this thread, but the timeline is completely up to you