Checking power supply to MAF sensor

Fig 1: Locating MAF Sensor

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• Disconnect 5-pin connector for MAF sensor - arrow  -.
• Switch ignition on.

Fig 2: 5-Pin Harness Connector & Terminals

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• Measure MAF sensor voltage supply between following connector terminals:

• Switch ignition off.

If no voltage is present:

• Remove wiper arms and plenum cover. →92 WINDSHIELD WIPER & WASHER SYSTEM

Fig 3: Identifying Test Box V.A.G 1598/22 Connected To Control Module Wiring Harness

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• Connect test box V.A.G 1598/22 (through my 1999) or test box V.A.G 1598/31 (from my 2000) to control module wiring harness.

Fig 4: 5-Pin Harness Connector & Terminals

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• Check wiring between test box and connector for open circuit according to wiring diagram.

• Wire resistance: max. 1.5 Ω

• Check wires for short to one another, to vehicle Ground and to battery positive (B+).

• Specification: ∞ Ω

If no wiring malfunction is detected:

• Replace engine control module → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing  .