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Circuit Test VAF - Vane Airflow Meter

Fig 1: VAF Meter Circuit & Connector Terminal ID
G91J08152
NOTE: Enter this test only when a Code 08 is displayed during self-test procedures (KOEO or KOER), or when directed here from another CIRCUIT TEST. To avoid unnecessary use of diagnostic time, check for unmetered air leaks between VAF meter and throttle body. This test is intended to diagnose only VAF and VMREF circuits.
CIRCUIT PIN IDENTIFICATION (VAF)

Circuit Breakout Box Pin No. ECA Pin Wire Color
1.8L
SIGRTN 46 & 49 2D Black/White
VAF 25 2O Red
VREF 26 2K Green/Red
2.2L Non-Turbo
M/T
SIGRTN 46 & 49 2D Green/Yellow
VAF 25 2O Red/Black
VMREF 6 2J Red/White
VPWR 37 & 57 1B Red/Black
A/T
SIGRTN 46 & 49 3D Green/Yellow
VAF 25 2B Red/Black
VMREF 6 2A Red/White
VPWR 37 & 57 1B Red/Black
2.2L Turbo
SIGRTN 46 & 49 3D Green/Yellow
VAF 25 2B Red/Black
VMREF 6 2A Red/White
VPWR 37 & 57 1B Red/Black

1) Checking System Integrity  Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Checking VAF Meter Voltage  Install breakout box. Turn ignition on. Measure voltage between VAF and SIGRTN test pins, while moving air door. If voltage is not within specification, go to step 4). See VOLTAGE SPECIFICATIONS (VAF METER)  . On 1.8L, if voltage is within specification, VAF meter and circuit are okay; fault is in another circuit or in ECA. On 2.2L, if voltage is within specification, go to next step.

3) VMREF Input Voltage  Turn ignition on. Measure voltage between VMREF and SIGRTN test pins. If voltage is 7-9 volts, VAF and circuit are okay; fault is in another circuit or ECA. If voltage is not 7-9 volts, repair VMREF circuit between ECA and VAF meter.

VOLTAGE SPECIFICATIONS (VAF METER)

Door Position Volts
1/8 Open 3.24
1/4 Open 5.60
3/8 Open 5.62
1/2 Open 5.83
5/8 Open 6.02
3/4 Open 6.57
7/8 Open 7.46
Fully Open 7.87

4) Checking Signal From VAF Meter  Locate VAF meter measuring vane and remove connector. On 1.8L engines, jumper SIGRTN and VREF connector terminals to matching terminals on VAF meter. On 2.2L engines, jumper SIGRTN, VMREF and VPWR connector terminals to matching terminals on VAF meter. Leave VAF circuit open. Turn ignition on. Measure voltage between VAF terminal at meter and SIGRTN terminal at harness connector while moving air door. Voltage should be as listed in VOLTAGE SPECIFICATIONS (VAF METER)  . On 1.8L engines, if voltage is not as specified, go to next step. On 2.2L engines, if voltage is not as specified, go to step 6). On all models, if voltage is as specified, repair VAF circuit between ECA and VAF meter.

5)  Voltage should be as listed in VOLTAGE SPECIFICATIONS (VAF METER)  . On 1.8L, if voltage is not as specified, go to next step. On 2.2L, if voltage is not as specified, go to step 7). On all models, if voltage is as specified, repair VAF circuit between ECA and VAF meter.

6) Checking VREF At VAF Meter  Turn ignition off. Remove VAF meter connector. Turn ignition on. Measure voltage between VAF wire and SIGRTN wire. If voltage is 4.5-5.5 volts, replace VAF meter. If voltage is not 4.5-5.5 volts, go to CIRCUIT TEST VREF.

7) VAF Signal Without VMREF  Locate air door of VAF meter. Turn ignition off. Remove meter connector. Using jumper wire, connect SIGRTN and VPWR terminals at connector to matching terminals on VAF meter. Leave VAF and VMREF circuits open. Turn ignition on. Measure voltage between VAF and SIGRTN terminals on VAF meter. As flap is moved, voltage should be as listed in VOLTAGE SPECIFICATIONS (VAF METER)  . If voltage is as specified, repair VMREF circuit between ECA and VAF meter. If voltage is not as specified, go to next step.

8) SIGRTN/VPWR At VAF Meter  Remove VAF meter connector. Turn ignition on. Measure voltage between VPWR terminal and SIGRTN terminal at connector. If voltage is greater than 10 volts, replace VAF meter. If voltage is less than 10 volts, measure voltage between VPWR terminal and ground. If voltage is more than 10 volts, repair SIGRTN wire between VAF meter and ECA. If voltage is less than 10 volts, go to CIRCUIT TEST VPWR.