JAGUAR XJ6 1994 2.G Electrical Diagnostic Manual

lw Automatic Transmission (AJ16)
TRACTION CONTROL INPUT ELECTRICAL - P 1782
The traction control input allows the ABS/TC CM, which performs the traction control function to inform theTCM when
traction control is in operation. This allows the TCM to select a specific shift pattern which increases the effectiveness
of the traction control.
The signal has two states; active and inactive. In the inactive state the line is pulled high by
a 1 k21 resistor in the TCM
and should rest at battery voltage. In the active state, the ABS /TC CM drives a square wave signal at 2.5 Hz ie on for 200ms, off for 200ms. During the off phase the voltage should be greater than battery voltage minus 1.5V and during
the on phase the voltage should be less than 1V.
Because traction control is not fitted to all vehicles the traction control input will be open circuit on some cars. Diagnos- tics are limited to detection of permanent short circuit to ground. Fault detection is triggered if the signal line voltage is less than 1.8V for longer than 200ms. If a fault is detected code P 1782 is stored and the traction control shift pattern
is inhibited. The diagnostic test is performed continuously during initialization and operation.
TCM ABS
/ TC CM
CC007/029 LS027/003 LHD
RS027/003 RHD
Possible causes:
Faulty harness wiring / connector.
. Faulty signal from ABS CM.
Effects:
. Traction control shift pattern disabled
Remedy:
Repair or renew harness / connector.
. Examine ABS /TC CM fault diagnosis (refer to EDM, section 12.1).
0
0
0
0
X300 EDM Issue 1 August 1994 18

0
0
Automatic Transmission (AJ16)
I
10
r
P29 7 I RP
'1 3
I
+12v T
n 1K21
1
I
r
n
J88-1791
Fig. 1 Fault Code PI782
X300 EDM 19 Issue 1 August 1994

w Automatic Transmission (AJ16)
TRANSMISSION WARNING LAMP - P 1785
The transmission warning indicator lamp is located in the instrument pack and is driven off by and active low signal
from the TCM. This means that if the TCM is not connected the warning lamp will be permanently illuminated.
This diagnostic runs continuously while in initialization and operation and will detect
a short circuit to battery or a short
circuit to ground on the input.
TCM
(CC007) BULKHEAD HARNESS (FC007) INSTRUMENT PACK (FCOOS)
PIN 16 -LAMP PIN 13 PIN 44
Possible causes:
Faulty wiring harness / connectors.
Faulty indicator lamp.
. Faulty instrument pack.
Effects:
. Permanent illumination of indicator lamp on instrument pack (if TCM or wiring faulty).
Remedy:
Repair or renew harness / connector.
Renew indicator lamp.
Examine instrument pack fault diagnosis (refer to EDM, section 15).
/I
b
M(t I
4r^
tl 1
11.1rn
Fig. 1 Fault Code P1785
Issue 1 August 1994 20 X300 EDM

Automatic Transmission (AJ16)
TP ELECTRICAL SIGNAL SYSTEM - P 1791
If the throttle angle signal line is held permanently high or low for more than looms, then this fault will be recognised
and stored. The TCM will adopt the substitute throttle value and turn on the warning lamp. The fault code will only be
stored if the engine speed is greater than 400rpm.
TCM PI HARNESS ECM
CC007/047 P1063/00 1 PI 1041032
Possible causes:
Faulty harness wiring I connection.
. Faulty ECM signal.
Effects:
Transmission warning lamp illuminated.
. MIL illuminated.
Normal mode only available.
Substitute throttle angle adopted.
No kickdown facility.
Remedy:
Repair or renew harness 1 connector.
Examine ECM fault diagnosis (refer to EDM, Section 5.1).
TP SIGNAL SYSTEM RANGE/ PERFORMANCE - P 1790
The throttle signal is a pulse width modulated (pwm) input which runs at a constant frequency of 183 Hz the information is contained in the duty cycle of the signal. If this information is out of range, that is, the duty cycle is less than 5% or
greater than 94%, then the TCM will use a substitute throttle value of 47% and will light the warning lamp and this fault code will be stored. During cranking, this signal is used to convey the engine coolant temperature. The coolant tem- perature signal persistsfor 500 msec after reaching the engine run threshold of 400 rpm. If theTCM does not recognise a valid throttle angle signal afterthis time then a substitute throttle value (47%) will be used and the warning lamp will
be
lit and this fault code will be stored. A fault code will only be stored if the engine speed is greater than 400 rpm. If an out of range coolant temperature is received then a substitute coolant temperature value (77" C) is used but no fault is stored.
X300 EDM 21 Issue 1 August 1994

4
ON PW
P473 P21* P32
1 K21
1 Kz1 B 31K6
-I-
31 K6 d rz:
(D 51 Kl
i
Fig. 1 Fault Codes PI790 / PI791
iw
6
U
1
P
a-1736
Issue 1 August 1994 22 X300 EDM

Automatic Transmission (AJ16)
SPORT MODE INDICATOR - P 1792
The sport mode lamp is located in the instrument pack. The input is 'pulled up' to nominal battery voltage (+12V) and
is supplied by an ignition switch feed. The TCM drives the signal to ground to turn the lamp on. The diagnostic runs
on the sport mode indicator output continuously during initialization and operation. The
checkcan detect an open cir- cuit, a short circuit to battery and short circuit to ground, although the diagnostic cannot distinguish between an open
circuit and a short to ground.
TCM
(CC007) BULKHEAD HARNESS (FC007) INSTRUMENT PACK (FCOO9)
PIN 49 - SPORT PIN 14
PIN 14
Possible causes:
. Faulty wiring harness I connectors.
. Faulty indicator lamp.
Faulty instrument pack.
Effects:
. No illumination of indicator lamp on instrument pack.
. Permanent illumination of indicator lamp on instrument pack.
Remedy:
. Repair or renew harness 1 wiring.
. Renew indicator lamp.
0 . Examine instrument pack fault diagnosis (refer to EDM, Section 15).
1
Y.IM
Fig. 1 Fault Code PI792 ~~
X300 EDM 23 Issue 1 August 1994

lw Automatic Transmission (AJ16)
SYSTEM VOLTAGE MALFUNCTION - P 1794
The TCM monitors the supply voltage and will log this fault if the voltage is less than 10.5V when the engine speed is
greaterthan 1600rpm. This fault code is unlikelyto becaused by afault within theTCM and assuch thevehicle harness
and fuses etc. should be completely tested before the TCM is condemned.
Possible causes:
. Blown fuses.
. Faulty harness wiring /connections.
Effects:
Transmission default settings adopted.
. MIL illuminated.
Transmission warning lamp illuminated.
. Maximum fluid pressure available.
. Limp home mode applied.
Remedy:
Examine fuse F14 in LH heelboard fuse-box. Renew (if necessary) after determining cause of rupture.
. Repair or renew harness / connector.
KICK-DOWN SWITCH SYSTEM - P 1796
The diagnostic check on the mode switch input is a plausibility check which is performed continuously while in oper- ation. A fault is determined when kickdown is seen when the throttle angle is less than 50%. However a fault will only
be logged if the output speed is greater than 256 rpm. No fault is logged if there is already a throttle signal fault. The
kickdown switch is located on the floor under the accelerator pedal and is operated when the throttle is fully open (ap- prox 90%). It is a normally open switch with one contact permanently to ground and the other is a signal to the TCM.
The signal wire is routed through the bulkhead harness and the gearbox harness to the TCM.
LHD
(FCO19) PIN 2 GROUND PIN 1 KD
SIGNAL
RHD
(CA074) PIN 2 GROUND PIN 1 KD
SIGNAL
Possible causes
. Faulty harness wiring /connections.
. Faulty switch (or switch adjustment).
Effects:
No kickdown facility.
Remedy:
. Repair or renew harness /connector.
. Re-adjust or renew switch.
0
0
0
Q
Issue 1 August 1994 24 X300 EDM

Automatic Transmission (AJ16) w
I
1 ---
I 9
I
I
0
1
JBd. 1737
Fig. 1 Fault Code PI796
X300 EDM 25 Issue 1 August 1994

Automatic Transmission (AJ16)
TCM FAULTS - PO603 / PO605 / P1608
0 Internal Control Module Keep Alive Memory Error - PO603
0 Internal Control Module ROM Test Error - PO605
0 Watch-dog Fault - PI608
Possible causes:
. Internal TCM circuit faults
Effects:
MIL illuminated.
. Transmission warning lamp illuminated (PO605 and PO1608 only).
. Maximum fluid pressure available (PO605 and PI608 only).
. Limp home mode applied (PO605 and PI608 only).
Remedy:
. RenewTCM.
Issue 1 August 1994 26 X300 EDM

Automatic Transmission (AJ16) w
8.1.5
nector.
TRANSMISSION CONNECTOR
(GB003)
TRANSMISSION ELECTRICAL PIN POINT TESTS
THE FOLLOWING TESTS describe methods of testing the transmission control solenoid valves from the multi-pin con-
0 A = Road Speed Sensor
0 B = Pressure Regulator
0 D = Oil Temperature Signal
0 F = Road Speed Sensor
0 H = MVI Solenoid
0 J = Oil Temperature Ground
0 K = MV2 Solenoid
0 L = MWVK Solenoid
0 M = Solenoid Supply
The solenoid valves are located on the valve block in the transmission assembly and can be identified by their position.
Connection is made via a connector located on the LHS of the transmission assembly.
Impedance Checks
M
-L)
M
-K) 28-60ohm
0 M-H)
M-B 5-70hm
M)(A
K)(D
L 1-( F O/C
H)(J
B)(
L-K)
L
- H ) 56- 120 ohm
K
-H)
L
-B)
K
-B) 33-67ohm
H
-B)
All Pins
- Ground OK
5
m- 1738
Fig. 1 Transmission Multi-plug Connector
X300 EDM 27 Issue 1 August 1994