Checking intake manifold sender — VW

1Z AHU
Special tools, testers, measuring instruments and auxiliary items required

Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3
Test box V.A.G 1598/18
Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
Adapter set V.A.G 1594
Current flow diagram

Test sequence

Connect fault reader V.A.G 1551 and select engine electronics control unit (address word 01); selection is carried out with engine idling.
=> Page
01-3

Rapid data transfer
HELP
Select function XX
Indicated on display:

Input 08 for "Read measured value block" function and confirm with Q.

Read measured value block
HELP
Input display group number XXX
Indicated on display:

Press keys 0, 0 and 7 for "Display group number 7" and confirm entry with Q key.

Read measured value block 7
"
15.4 5C
15.9 5C
16.7 5C
Indicated on display:

Observe display in display zone 3.

If faulty the following substitute values will be displayed:
Engine code 1Z, AHU: 18.9 °C
Engine code AFN: 136.8 °C

If no realistic value is displayed in display zone 3 or the substitute is displayed. Check intake manifold temperature sender and wiring to sender as follows:

Electrically checking intake manifold temperature sender (G72)

Switch off ignition.
Pull connector off sender =>Fitting locations overview, Page
23-4
.

Carry out resistance measurement between contacts using hand multimeter V.A.G 1526.

Specifications =>Illustration

Scale A shows resistance values for temperature range 0...50 °C and scale B the values for temperature range 50...100 °C.

Examples:

30 °C corresponds to a resistance from 1500...2000 ω
80 °C corresponds to a resistance from 275...375 ω

If the specification is not attained:

Replace intake manifold temperature sender (G72).

Checking wiring connection to intake manifold temperature sender (G72)

Switch off ignition.
Pull connector off sender =>Fitting locations overview, Page
23-4
.
Connect test box =>Page
23-34
.

The following wiring connections are to be checked for open circuits and/or short to positive or negative.

Wiring from connector contact 2 to test box socket 33.
Wiring from connector contact 1 to test box socket 64.
Rectify any open/short circuit as necessary.
If neither an open or short circuit exists, renew Diesel direct injection system control unit.