DTC 01268
DTC Code 01268, Quantity Adjuster N146:Control Difference
The Quantity Adjuster is an electro-magnetic swivelling positioner which is ECM controlled via duty cycle. The eccentric shaft on the Quantity Adjuster moves the modulating piston against the high pressure pistons which in turn regulates the injection quantity
Special Tools, Testers And Auxiliary Items:
- VAG 1598/18 Test Box adaptor
- Fluke 83 Multimeter or equivalent
- VW 1594 Adaptor kit
- Wiring diagram
Work Sequence:
Display will appear as shown:
Rapid data transfer HELP
Select function XX
- Press 0 and 8 buttons to select Function 08 "Read measuring value block"
- Press Q button to enter input
Display will appear as shown:
Read measuring value block HELP
Input display group number XX
- Press 0 and 1 buttons to select "display group 01"
- Press Q button to enter input
Display will appear as shown:
Read measuring value block 1 -->
840 rpm 6.6 mg/H 1.480 V 87.3°C
- Observe Engine Coolant Temperature display in channel 4
Specification: 85°C minimum
- Continue when specification is obtained
Display will appear as shown:
Read measuring value block 1 -->
840 rpm 6.6 mg/H 1.480 V 87.3°C
- Observe voltage from Modulating Piston Displacement sensor G149 in channel 3
Specification: 1.250 to 1.750 Volts
If specified voltage not obtained:
- Press -> button
- Press 0 and 6 buttons to select Function 06 "End data transfer"
- Press Q button to enter input
- Switch OFF ignition
- Disconnect Quantity Adjuster N146 harness connector connector to injection pump quantity adjuster
- Measure resistance between harness connector terminals 5 + 6
Specification: 0.5 to 2.5 ohm
If specified resistance not obtained
- Replace injection pump
If specified resistance obtained:
- Connect VAG 1598/18 Test Box adaptor to ECM wiring harness connector -1-
- Check wiring for open circuit between VAG 1598/18 Test Box adaptor and harness connector using wiring diagram:
Terminal 5 + sockets 23, 45 and 68
Terminal 6 + sockets 4, 5 and 49
Wire resistance: 1.5 ohm maximum
- Check for shorting between wires
Specification: infinite ohms
If no malfunction found:
- Replace ECM J248