1994 JAGUAR XJ6 fuse

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

E I ect r ical n
-
Electrical schematic - Fault Code 13
0
0
0
+12v
+12v
I_i
I 10
4
1. Instrument Panel Fuse 6. Passenger-side Air Bag
2. Engine Compartment Fuse 7. RH Impact Sensor
3. Safing Sensor 8. LH Impact Sensor
4. Cable Reel Cassettes 9. Air Bag MIL Lamp 5. Driver-side Air Bag 10. Diagnostic Module
Fig. 1
586-1668
X300 EDM 15.1 - 13 Issue 1 August 1994

Electrical I3
FAULTCODE 14
Front Impact Sensor Circuit Shorted to Ground
Normal Operation
The DM monitors voltage level at pins 2 and 6. If this voltage falls to 5 volts, or less, the MIL Lamp will illuminate and
fault code 14 will be present, indicating a short circuit to ground on either of the two front impact sensorcircuits. During
the presence of fault code 14 the DM internal thermal fuse will blow, disabling the air bag deployment circuit. If voltage
to pins
2 and 6 is restored after the fuse has blown,fault code 51, open internal fuse will be present. Fault code 14 will
be present only as long as the short to ground remains.
Possible Causes
Short to ground in any of the following circuits:
0 Front impact sensor wiring.
0 Disconnection, or poor connection of harness.
0 Front impact sensors internal ground.
Fault Diagnosis
1. Sub-circuit identification
. Disarm SRS system.
. Remove plastic locking wedge from the grey DM connector.
. Measure resistance between connector pin 3 and all of the following pins; 2,6, 17 and 18.
9 Does any resistance reading indicate short circuit ?
Yes - Renew faulty sensor.
No - Examine sensor wiring harness, locate and rectify faults as necessary.
Proceed to fault code 51 on successful diagnosis.
rm
0
0
0
0
X300 EDM Issue 1 August 1994 15.1 - 14

Electrical rl
Electrkal schematic - Fault Code 14
0
0
0
0
J86-1667
1. Instrument Panel Fuse 6. Passenger-side Air Bag
2. Engine Compartment Fuse 7. RH Impact Sensor 3. Safing Sensor 8. LH Impact Sensor 4. Cable Reel Cassettes 9. Air Bag MIL Lamp
5. Driver-side Air Bag 10. Diagnostic Module
Fig. 1
X300 EDM 15.1 - 15 ~~ Issue 1 August 1994

E I ect r ica I rl
Electrkal schematic - Fault Code 2 1
0
0
0
0
2 P15 P23 PI 6
i I
10
1. Instrument Panel Fuse 6. Passenger-side Air Bag 2. Engine Compartment Fuse 7. RH Impact Sensor
3. Safing Sensor 8. LH Impact Sensor 4. Cable Reel Cassettes 9. Air Bag MIL Lamp
5. Driver-side Air Bag 10. Diagnostic Module
Fig. 1
J86-1668
X300 EDM 15.1 - 17 Issue 1 August 1994

Electrical IT
Electrical schematic - Fault Code 22
0
0
0
PO'
A A . P15 P23 P16
c-
PO9
PI E
P13 N
PO3 I
10
RP I
4
'I
15
1
4
J86-1669
1. Instrument Panel Fuse 6. Passenger-side Air Bag
2. Engine Compartment Fuse 7. RH Impact Sensor 3. Safing Sensor 8. LH Impact Sensor
4. Cable Reel Cassettes 9. Air Bag MIL Lamp
5. Driver-side Air Bag 10. Diagnostic Module
Fig. 1
X300 EDM 15.1 - 19 Issue 1 August 1994

Electrical rl
Electrical schematic - Fault Code 23
0
0
0
-I
YG
f
P13
10
1. Instrument Panel Fuse
J86-1670
6. Passenger-side Air Bag 2. Engine Compartment Fuse 7. RH Impact Sensor 3. Safing Sensor 8. LH Impact Sensor 4. Cable Reel Cassettes 9. Air Bag MIL Lamp 5. Driver-side Air Bag 10. Diagnostic Module
Fig.
1
X300 EDM 15.1 - 21 Issue 1 August 1994

Electrical
0
FAULT CODE 24
Safing Impact Sensor Output Feed / Return Open Circuit
Normal Operation
The DM measures voltage level at pins 11 and 12 which varies in accordance with battery voltage. DM calculates what
the value at pins 11 and 12 should be from the value measured at pin 13, battery voltage. If voltage measured at pins 11 and 12 is not as expected by DM the MIL Lamp will illuminate and fault code 24 will be present, indicating a safing
sensor circuit fault.
Vbatt
9.0 9.5 1 10.0 10.5
11.0 i 11.5 12.0 12.5 I 13.0 13.5 14.0
14.5 15.0
15.5
Vpin 2.3 2.4 ~ 2.5
2.7
2.8 ~ 3.0
3.1 3.2 1 3.4 3.5 3.7 3.8 4.0
4.1
Possible Causes
0 Air bag wiring fault.
0 Safing impact sensor wiring fault.
0 Grounding of air bag /sensor circuits.
0 Intermittent battery voltage at DM pin 13.
16.0 4.3
Fault Diagnosis
1. Voltage - check
8 Disarm the SRS system.
8 Turn ignition switch OFF, then ON.
8 Measure the voltage between DM pins 11, 12 and pin 3 (ground) and compare to following table.
Are voltages within
0.5V of normal ?
Yes -
8 Check battery +ve input voltage wiring to DM pin 13.. Rectify wiring faults, if any.
8 Check fuse F17 in RH fuse-box, renew if blown.
8 Check battery, renew if necessary.
8 Renew DM if no other faults are located.
8 Proceed to step 2 if both voltages are low.
8 Proceed to step 3 if only one voltage is low.
N
O -
2. Resistance -check
8 Switch off the ignition
and disconnect battery earth lead.
8 Disconnect DM and measure resistance between pin 11 and pin 3.
8 Does resistance value indicate open circuit ?
Yes - Renew DM.
No
-Examine wiring andcomponents insafing sensor, air bag and primarysensorcircuitsforshortstoground. Rectify
faults as necessary.
3. Sensor - check
8 Switch on the ignition.
8 Disconnect safing sensor from main harness and measure resistance across connector wires YP and RN.
8 Is resistance less than 29 ?
Yes - Examine harness wiring for open circuit. Rectify faults as necessary.
No - Renew safing sensor.
4. On completion
8 Arm and verify the SRS system.
X300 EDM Issue 1 August 1994 15.1 - 22