Multec (X 12 SZ / X 16 SZ) F0: DATA LIST
| No. | TECH 1 Display | Conditions for Checking | Nominal Value | Trouble Codes | Terminal |
|---|---|---|---|---|---|
| 08 | IDLE AIR CONTROL | Engine running at idle speed, operating temperature |
Note:
If 8 steps are not attained or 26 steps are exceeded (at idle speed without load) for longer than 10 s, the control unit resets the stepper motor after ignition OFF. After an interval of 5 s, re - start the engine. If, after this procedure, the number of steps is less than 8 or greater than 35, initiate trouble - shooting.
If the number of steps continues to border around 26 (24 to 28), ensure by switching on load (lamp, rear screen heating, selector lever in position "D") that 26 steps are exceeded for longer than 10 s. Then proceed as described above.
| 8 to 26 steps | 35 | C 5, C 6, C 8, C 9/D 1/ | |
|---|---|---|---|
| Trouble - shooting: | Nominal Value: | Cause of Fault: |
(If nominal value is not attained)
· Slowly increase speed up to 4000 rpm by actuating the accelerator cable, hold briefly and let it sink to idle speed once again.
· Wait approx. 5 s.
| Vehicle with MT | · Carry out test step 04. |
Vehicle with AT
| Engage parking brake | 900 rpm |
Selector lever position "P", "N"
| "R", "D", "3", "2", "1 | 775 rpm |
700 rpm
· Select TECH 1 mode "F8"
| · Using arrow keys, increase (1500 rpm) and decrease (1000 rpm) idle speed | Engine speed increases and decreases | · Throttle valve gap too large or too small, (basic setting: alter only in emergencies, see next page but one). |
· Engine takes in dead air.
| · Trouble code 21 and 22 set. |
· Ignition OFF
· Disconnect plug from idle speed regulator M 66.
· Ignition ON
· TECH 1 in mode "F5" IDLE AIR CONTROL
· Measure voltage:
from: wiring harness plug Ter. A
to: wiring harness plug Ter. B
| greater than 11 V |
from: wiring harness plug Ter. C
| to: wiring harness plug Ter. D | greater than 11 V | · Carry out visual check on plug connections. |
· Wiring harness defective.
· Control unit defective.
· Lead interruption,
from: control unit K 57
to: idle speed regulator M 66
· Ignition OFF
· Measure resistance of coils A - B and C - D
| 55 W to 65 W (cold) | |
|---|---|
| 45 W to 60 W (warm) | · Idle speed regulator defective |
· Ignition OFF
· Remove motor M 66
· Connect plug to idle speed regulator M 66
· Ignition ON
TECH 1 in mode "F5" IDLE AIR CONTROL
| Compress valve cone lightly with thumbs | Valve cone moves visibly in and out | · Idle speed regulator defective |
|---|---|---|
| · Additional Causes | · Loose contact in throttle valve potentiometer |
· Throttle shaft out of alignment
· Throttle valve gap too large or too small, (basic setting: see next section).
· Engine takes in dead air.
· Idle speed regulator seat soiled.
· Exhaust gas recirculation valve mechanically blocked
· Fault in evaporation control system
· Spark plugs defective
· Mixture too lean or too rich.
· Battery voltage too high / low
| · Odometer frequency sensor / instrument defective or circuit defective. |
Basic adjustment of throttle valve, see Service Instructions (alter in emergency only)