Volkswagen Jetta 1999 MK4 GLS 2.0L

SENELA

MEMBER
1999 VOLKSWAGEN JETTA
4 CYL
FWD
AUTOMATIC
145,000 MILES

This car cranks but will not start. Changed coil pack, spark plugs, wires. Fuel line and injectors are OK. Narrowed problem down to some kind of electrical problem. Something seems to be shorting the electrical system. Run diagnostics came up with:

1.16706 - Engine Speed Sensor (G28): No Signal
P0322 - 35-10 - - - Intermittent
2.00518 - Throttle Position Sensor (G69)
16-00 - Signal Outside Specifications
3.00529 - Engine Speed Signal Missing
35-00 - -
4.00545 - Engine-Transmission ElectricalConnection
31-00 - Open or Short to Ground
5.01314 - Engine Control Module
49-00 - No Communications
6.01312 - Powertrain Data Bus
49-00 - No Communications

Can someone help me diagnose this? How do I trace the shorting component? - I know there is a short because the stock radio promptly blows it's fuse whenever I replace it.

Thanks a lot

2 Replies

BMRFIXIT

MECHANIC
19,053 POSTS

The engine speed (RPM) sensor -G28- detects engine speed and reference marks. Without an engine speed signal, the engine will not start. If the engine speed signal fails while the engine is running, the engine will stop immediately.

Engine Speed (RPM) Sensor (2.0L) Located On left side of engine block, near transmission flange

Disconnect gray 3 -pin harness connector (arrow) to the engine speed (RPM) sensor.
Measure sensor resistance between terminals 2 + 3 at connector to sensor.
Vehicles with engine code AEG: Specified value: 480.1000?
Vehicles with engine code AVH, AZG: Specified value: 730.1000?

Check sensor for shorts between terminals 1 + 2 and 1 + 3.
Specified value: INFINITY?
If specified values are not obtained:
Replace Engine Speed (RPM) Sensor -G28-:

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