1994 JAGUAR XJ6 charging

Electrical IT
SECTION CONTENTS
Sub
-Section 15.2 lnsfrumenfs
Subsection Title SRO Page
15.2 ............. Instruments .................................................................... 15.2-1
15.2.1
............ Introduction .................................................................... 15.2-1
15.2.2
............ Instrument Pack Connectors - Pin Locations ......................................... 15.2-3
15.2.3
............ Component Description .......................................................... 15.24
15.2.3.1 .......... Speedometer ................................................................... 15.24
15.2.3.2 .......... Tachometer .................................................................... 15.24
15.2.3.3
.......... Engine Oil Pressure and Warning Lamp ............................................. 15.24
15.2.3.4 .......... Engine Coolant Temperature ...................................................... 15.24
15.2.3.5 .......... Fuel Tank Level Gauge and Warning Lamp .......................................... 15.24
15.2.3.6
.......... Battery Voltage Gauge and Warning Lamp .......................................... 15.24
15.2.3.7
.......... Liquid Crystal Display ........................................................... 15.24
15.2.3.8 .......... Trip Computer .................................................................. 15.2-5
15.2.4
............ Primary Warning Lamps (Illuminated Red) .......................................... 15.2-5
15.2.4.1
.......... Exhaust Temperature ............................................................ 15.2-5
15.2.4.2
.......... Low Oil Pressure ................................................................ 15.2-5
15.2.4.3
.......... Seat Belt ....................................................................... \
15.2-5
15.2.4.4
.......... Trunk Lid Open ................................................................. 15.2-5
15.2.4.5
.......... DoorAjar ...................................................................... 15.2-5
15.2.4.6
.......... Engine Coolant LeveL ............................................................ 15.24
15.2.4.7
.......... SRS Airbag Fault ................................................................ 15.24
15.2.4.8 .......... Charging Fault .................................................................. 15.24
15.2.4.9 .......... Brake System Fault .............................................................. 15.24
15.2.4.10 ......... Bark Brake ..................................................................... 15.24
15.2.5. ........... Secondary Warning Lamps (Illuminated Amber) ...................................... 15.2-7
15.2.5.1
.......... Transmission Fault ............................................................... 15.2-7
15.2.5.2
.......... Washer Fluid Level .............................................................. 15.2-7
15.2.5.3
.......... Bulb Fail ....................................................................... \
15.2-7
15.2.5.4
.......... Traction Control Fail ............................................................. 15.2-7
15.2.5.5
.......... Anti-lock Fail .................................................................. 15.2-7
15.2.5.6
.......... Low Fuel Level ................................................................. 15.2-7
15.2.5.7
.......... Check Engine ................................................................... 15.2-7
15.2.6.1
.......... Transmission Sport Mode ......................................................... 15.2-8
15.2.6.2
.......... Traction Control OFF ............................................................ 15.2-8
15.2.6.3
.......... Direction Indicators ............................................................. 15.2-8
15.2.6.4
.......... Main Beam .................................................................... 15.2-8
15.2.6
............ Status
and Warning Lamps ........................................................ 15.2-8
m
a
0
e
0
X300 EDM ii Issue 1 August 1994

n E I ectr ica I
FAULT CODE 12
Low Battery Voltage
Normal Operation
The DM monitors voltage at pin 13 which should be equal to battery voltage. If a voltage lower than 9V is detected at pin 13 the MIL Lamp will illuminate and fault code 12 will be present.
Possible Causes
Drop in battery voltage to DM pin 13 caused by:
0 Open circuit to pin 13 from battery.
0 Short circuit to ground on battery feed circuit.
0 Safing sensor feed shorted to ground.
0 Safing sensor internal short to ground.
0 Faulty charging system draining battery voltage.
Fault Oiagnosis
1. Battery voltage test
Disarm the SRS system.
8 Disconnect the DM.
8 Switch on the ignition.
Measure the voltage between DM connector pin 13 (+ve) and pin 3(-ve).
If battery voltage is present at pin 13, renew the DM.
8 Arm and verify the SRS system.
8 If battery voltage is not present, go to step 2.
2.
Fusecheck
8 Check fuse 17 in the RH fuse-box.
If the fuse has blown, check for short circuit to ground between fuse and pin 13 DM connector.
8 Renew the fuse, go to step 3.
8 If the fuse has not blown, check for open circuit between battery positive terminal and pin 13 DM connector.
3. Short circuit check
* Switch off the ignition.
8 Connect the DM.
8 Has the fuse blown 1
Yes -
= Short circuit to ground from pin 15 DM (R/ W) to pin 3 safing sensor, or from pin 23 DM (Y / P) to pin 6 safing sensor.
8 Intermittent short circuit to ground; check wire (R / W) from pin 15 DM to pin 3 safing sensor, and, wire (Y/ P) from
NO -
pin 23 DM to pin 6 safing sensor.
4. On completion
8 Renew the fuse as necessary.
8 Arm and verify the SRS system.
Issue 1 August 1994 15.1 - 10 X300 EDM

rl Electrical
FAULTCODE 13
Air Bag Shorted to Ground
Normal Operation
The DM monitors voltage level at pins 11 and 12 which varies in accordance with charging voltage. If voltage measured
at these two pins falls below 2V the MIL Lamp will illuminate and fault code 13 will be present, indicating a possible
short to ground.
During the presence of fault code 13 the DM internal thermal fuse will blow, disabling the air bag deployment circuit.
If voltage to pins 11 and 12 is restored after the fuse has blown, fault code 51, open internal fuse,
will also be present.
Fault code 13 will be present only as long as the short to ground remains.
Possible Causes
Short to ground in any of the following circuits:
0 Air bag supply wiring.
0 Air bag internal.
0 Cable reel cassette internal.
0 Safing sensor supply wiring.
0 Safing sensor internal.
Fault Diagnosis
1. Air bag(s) -short circuit
. Disarm the SRS system.
. Disconnect both air bag modules multi-plug connector.
. Switch ignition ON.
. Is fault code 13 still present ?
Yes - Proceed to step 2.
No - Proceed to step 3.
2. Cable reel cassette
-short circuit
Examine wiring and connector where cable reel cassette mates to the main harness, below the steering column.
If a fault cannot be located, disconnect cable reel cassette from main harness.
. Connect air bag simulator to the main vehicle harness in place of the cable reel cassettes.
. Measure resistance between pin 11 DM and pin 3 (ground).
. Is pin 11 short circuit to ground ?
No - Proceed to fault code 51.
Yes
- Examine wiring and connections between DM, both air bags and safing sensor. Rectify faults as necessary.
If a fault is located, rectify and proceed to step 3.
3. Air bag modules
-check
. Ensure shorting bar is correctly installed to passenger-side air bag connector.
. Measure resistance between connector terminals and module casing.
If resistance value shows a short to ground, renew the module.
. If resistance shows open circuit, repeat test for driver-side module, renew as necessary.
Proceed to fault code 51 on successful diagnosis.
Issue 1 August 1994 15.1 - 12 X300 EDM

rl E I ect r ica I
Vbatt 1 9.0 9.5
10.0 10.5
11.0 11.5 12.0 12.5 ~ 13.0
13.5
Vpin
I 2.3 2.4 2.5 2.7 2.8 3.0 3.1
3.2 1 3.4 3.5
FAULT CODE 22
Safing Impact Sensor
Output Circuit Shorted to Battery Voltage
Normal Operation
The DM measures voltage level at pins 11 and 12 which varies in accordance with charging voltage. If voltage
measured at these two pins exceeds
5V the MIL Lamp will illuminate and fault code 22 will be present, indicating a short
to battery voltage.
14.0 14.5 15.0 15.5 16.0
3.7 3.8 4.0
4.1 4.3
Possible Causes
0 Air bag supply
wiring faulty.
0 Safing impact sensor supply wiring faulty.
0 Safing impact sensor internal contacts short circuit.
0 Cable reel cassette faulty
0 Charging system voltage too high (above 17V).
2. Resistance - check
. Measure resistance across safing sensor contacts.
. Does resistance value indicate open circuit.
Yes
-Examine harness wiring for short circuits. Rectify faults as necessary.
No - Renew safing sensor.
3. On completion
Arm and verify the SRS system.
0
0
0
0 ~
issue 1 August 1994 15.1 - 18 X300 EDM

E I ect r ical
15.2.3 COMPONENT DESCRIPTION
15.2.3.1 Speedometer
The speed indication input signal, sent as a pulse rate, is generated by an open collectortransistor within the ABS con- trol module. The instrument pack converts the frequency of this signal to drive the speedometer and to provide two
road speed outputs:
Speed output
1 (pin 2,48 way connector)
This output is connected to the radio head unit, security control module and the power steering module.
Speed output 2 (pin
3,48 way connector)
This output is connected to the body processor unit, cruise control control module, air conditioning control module
and the engine management system.
15.2.3.2 Tachometer
The tachometer input, all engine variants, is provided by the engine management control module. When the engine
is running the control module generates three high state pulses per engine revolution.
15.2.3.3
This signal comes direct from the variable resistance type oil pressure sensor, mounted on the engine. The sensor
resistance values range from 75Q (8 Bar) to 330Q (0 Bar).
When the gauge reaches
a pre-determined reading the instrument pack illuminates the warning light.
Engine Oil Pressure and Warning lamp
15.2.3.4 Engine Coolant Temperature
This signal comes direct from the coolant temperature sensor (variable resistance type), mounted on the engine. The
sensor resistance values range from 34Q (hot) to 241Q (cold), when disconnected from the vehicle.
Note: The coolant temperature gauge is calibrated to indicate at approximately 'Normal' for a wide range of normal
engine operating temperatures.
15.2.3.5 Fuel Tank level Gauge and Warning lamp
This signal (pin 20,24-way connector) comes direct from the variable resistor type fuel level sensor. The sensor resis- tance values range from 80 ohms (full tank) to 900 ohms (empty tank).
When the gauge reaches a pre
-determined reading, the instrument pack illuminates the warning lamp.
15.2.3.6
Battery voltage is displayed on the gauge by measuring the ignition voltage.
The red charge warning lamp will illuminate if either the voltage is too low (below
10.5V) or too high (above 15.5V). In addition, the generator provides a low signal to the instrument pack (pin 9,48-way connector) when battery charging
is unsatisfactory.
Battery Voltage Gauge and Warning lamp
15.2.3.7 Liquid Crystal Display
A single line, six digit, 7 segment display with six trip function flags used for odometer, trip computer and driver mess- ages.
!Y,Q&: If the instrument pack has not been PECUS programmed, the back illumination of the LCD will not switch on.
Check that a PECUS label is attached to the back of the pack.
Issue 1 August 1994 15.2 - 4 X300 EDM

E I ect r ica I
15.2.4.6 Engine Coolant Level
This signal (pin 37,48-way connector) comes from the coolant level switch, mounted in the lower face of the coolant
header tank. The switch is normally in the closed position, providing
a low signal to the instrument pack, when the
coolant level is acceptable. If the coolant level drops, the switch will open, removing the low signal and illuminating
the indicator lamp.
15.2.4.7 SRS Air bag fault
The input signal (pin 45, 48 way connector) is provided by the SRS Diagnostic Module.
WARNING: REFER TO SECTION 15, SUPPLEMENTAL RESTRAINT SYSTEM, BEFORE AlTEMPTlNG ANY DIAGNOSTIC
WORK ON SYSTEMS ASSOCIATED WITH THE
SRS.
15.2.4.8 Charging Fault
Battery voltage is displayed on the gauge by measuring the ignition voltage.
The red charge warning lamp will illuminate if either the voltage is too low (below
10.5V) or too high (above 15.5V). In addition,the generator provides a low signal to the instrument pack (pin 9,48-way connector) when battery charging
is unsatisfactory.
15.2.4.9 Brake System Fault (red)
The brakesystem fault receives a signal (pin 10,4&wayconnector)from the fluid level switch located in the brake fluid
reservoir. The switch is normally in the closed position, providing a low signal to the instrument pack, when the brake
fluid level is acceptable. If the fluid level drops, the switch will open, removing the lowsignal and illuminating the indi
- cator lamp.
15.2.4.10 Park Brake (red)
Park brake warning is indicated on application of the brake, which closes a micro-switch within the park brake handle
assembly. The signal to the instrument pack (pin 17, &way connector) is low when the park brake is applied and il- luminating the indicator lamp.
Issue 1 August 1994 15.2 - 6 X300 EDM