Opel Frontera UBS. Manual - part 2541

AUTOMATIC TRANSMISSION (AW30-40LE)

7A–27

DTC P0120 (FLASHING CODE 21) ANALOG THROTTLE SIGNAL FAILURE (VTH)

DTCP0120

7A–28

AUTOMATIC TRANSMISSION (AW30-40LE)

DTC P0502 (FLASHING CODE 24) SPEED METER SENSOR FAILURE (SP1)

D07RY00024

Circuit description:
Speed information is provided by the speed meter sensor
to the meter.
In the meter, the pulses of the speed meter sensor are
converted to speed signals (pulses), and these signals
are output to the TCM. The TCM converts these pulse
voltages to km/h signals.

Fail-safe control:
The TCM controls fail-safe by detecting speed meter
signal failure.

Failure detection:

• When not even 1 pulse is input in the speed meter

signal during the time 100 pulses are input in the
output revolution sensor signal.

• When not even 1 pulse is input in the speed meter

signal during the time 27 pulses are input in the
output revolution sensor signal.

Contents of control:
At failure detection

•Keeps the condition of transfer (High/Low judgment)

just before detection until vehicle speed is 0km/h,
and changes shift map to L4 map (3

→

4 UP None) at

vehicle speed is 0km/h.

• Uses high oil temperature map according to shift

map priority at correct oil temperature control.

• Up hill and down hill control inhibit.

• Stores the failure information in failure -memory.

• The failure detection of oil temperature sensor inhibit

At failure decision

Executes following items in adition to above control
items at failure detection.

•Blinks "CHECK TRANS" lamp

Conditions of turning "CHECK TRANS" lamp off: 
Turns "CHECK TRANS" lamp off when judged 0km/h by
speed meter sensor after more than 1 pulse are input in
the speed meter signal during the time 27 pulses are

input in the output revolution sensor.

Reversion conditions from fail-safe:
At failure detection and decision
Recovers at the same time as the conditions of turning
“CHECK TRANS” lamp off are satisfied.

Test description:

The following numbers correspond to circled numbers on
the diagnostic chart.

(1) The cause of DTC P0502 setting is due to the

operation fault of the speed meter.

(2) Speed signals are output from the meter. The sensor

power supply is given from the TCM.

Diagnostic aids:
An intermittent may be caused by a poor connection,
rubbed through wire insulation or a wire broken inside
the insulation. Inspect related harness connector for
backed out terminals, improper mating, broken locks,
improperly formed or damaged terminals, poor terminal
to wire connection and damaged harness.

AUTOMATIC TRANSMISSION (AW30-40LE)

7A–29

DTC P0502 (FLASHING CODE 24) SPEED METER SENSOR FAILURE (SP1)

DTCP0502

7A–30

AUTOMATIC TRANSMISSION (AW30-40LE)

DTC P0705 (FLASHING CODE 17) GEAR SELECTOR FAILURE (PRND2L)

D07RY00022

Circuit description:
The neutral start switch gives the signals related to the
selector lever position (PRND2L) to the Transmission
Control Module (TCM). The neutral start switch turns on
when the select lever  is shifted to the P, R, N, D, 2 or L
range. The neutral start switch, which is connected to the
starter switch circuit, is available only when the select
lever is in the P or N range
The neutral start switch is connected to the transmission
manual shaft and installed in the transmission case.

Fail-safe condition:
The TCM controls fail-safe by detecting selector position
switch failure.

Failure detection:

(1) OPEN: 

• When all switches are OFF

• When the failure criteria continues for 30 seconds

if the vehicle speed which is calculated by output
revolution sensor is more than 30 km/h and the
engine revolution is more than 1500 rpm.

(2) SHORT: 

• When more than two switches are ON at the same

time.

• When the failure criteria condition for 10 seconds.

Contents of control:
At failure detection

(1) OPEN: D range judgment

(2) SHORT: Judged by priority D>2>L>R>N>P

•Up hill and down hill control inhibit

•Winter mode inhibit

At failure decision

Excutes following items in addition to above control
items at failure detection.

•Blinks "CHECK TRANS" lamp

•Stores the failure information in failure-memory

•Reverse lockout control inhibit

Conditions of turning “CHECK TRANS” off:
Turns “CHECK TRANS” lamp off when only one of all
switches is ON.

Reversion conditions from fail-safe:
Turns “CHECK TRANS” lamp off when only one of all
switches is ON.
Test description:

The following numbers correspond to circled numbers on
the diagnostic chart.

(1) It is judged whether the input signal received from

the neutral start switch by the TCM is proper or not.

(2) The power status of the neutral start switch is

checked.

(3) The continuity between neutral start switch terminals

and the continuity of the wire connected to the
neutral start switch are checked.

Diagnostic aids:
An intermittent may be caused by a poor connection,
rubbed through wire insulation or a wire broken inside
the insulation. Inspect related harness connector for
backed out terminals, improper mating, broken locks,
improperly formed or damaged terminals, poor terminal
to wire connection and damaged harness.