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15.2.8 INSTRUMENT PACK PIN-POINT TESTS
15.2.8.1 Oil Pressure, Battery Condition, Coolant Temperature and Fuel Gauges
Gauge reads zero, full scale, too high or low
1.
2.
3. Oil
pressure and coolant gauges only; check relevant fluid level is within limits, top up if required and re-check
indication. If fluid levels are within limits on checking proceed to step 2.
Check connections to sensor are correct and secure. For battery gauge only check battery voltage is present at the
battery terminal posts.
Check resistance of sensor (if applicable) to ground, correct readings are as detailed in the following table:
Sensor title Resistance value
Oil pressure 3108 - 3308
Temperature
Fuel level 3461
(warm engine)
- 2418 (cold engine)
8061 (full tank) - 9008 (empty tank)
If resistance is out of range renew sensor.
If sensor resistance is proved correct, check the harness wiring continuity between the sensor and instrument pack
pin as detailed in the table below:
4.
I Sensor title I Instrument pack pin !
I Oil pressure I 21 (24-way connector) I Temperature I 19 (24-way connector) I
Fuel level 120 (24-way connector)
For battery condition gauge, checkvoltage between instrument pack 24
-way connector pins 2 and 4 is 13 f 2.5V. Refer to Section 15.5 for battery diagnostics.
If all previous checks prove correct remove and open the instrument pack. Examine flexi-circuit connections to
relevant gauge, ensuring correct and secure fitment.
Check continuity of flexi
-circuit tracks to gauge connections.
Check continuity of gauge driver windings by disconnecting gauge from flexi
-circuit and testing between the
upper central connection pin and each of the other two pins. If open circuit is recorded renew gauge.
5.
6.
7.
Gauge fluctuates
or gives erratic readings
1. Carry out steps 1 -4 above.
2.
Fit new sensor (where applicable) and re-check gauge.
3. Carry out steps 5
- 7 above
15.2.8.2 Speedometer
Gauge reads zero, full scale, too high or low
1.
2.
3.
4.
5. Refer
to Section 12,
ABS / Traction Control for fault diagnosis of wheel speed sensor.
Check harness wirin and connection from Instrument pack pin 15 (24
-way connector) and ABS /Traction Control
Control Module (AB!! /TC CM).
If all previous checks prove correct remove and open the instrument pack. Examine flexi
-circuit connections to
speedometer, ensuring correct and secure fitment.
Check continuity of flexi
-circuit tracks to speedometer connections.
Check continuity of speedometer driver windings by disconnecting from flexi
-circuit and testing between the
upper central connection pin and each of the other two pins. If open circuit is recorded renew speedometer.
6 15.2.8.3 Tachometer
Gauge reads zero, full scale, too high or low
1.
2.
3.
4.
5. Refer
to Section 5, Engine Management for fault diagnosis of tachometer signal.
Check harness wiring and connection from Instrument pack pin
24 (24-way connector) and Engine Management
Control Module (ECM).
If all previous checks prove correct remove and open the instrument pack. Examine flexi-circuit connections to
tachometer, ensuring correct and secure fitment.
Check continuity of flexi
-circuit tracks to tachometer connections.
Check continuity of speedometer driver windings by disconnecting from flexi
-circuit and testing between the
upper central connection pin and each of the other two pins, If open circuit is recorded renew tachometer.
15.2.8.4 Liquid Crystal Display
No (or patchy) illumination
1.
2. If no illumination check rear of instrument pack for attachment of 'PECUS' label. If label is not present then pack
will not have been programmed.
Check bulbs in rear of LCD module, renew as necessary.
Missing or Corrupt Segments
1. Switch ignition off, leave off for a minimum of 5 minutes, switch on and re-check panel display.
2. If display is still faulty remove instrument pack from vehicle and checkconnections between flexi-circuit and LCD
module.
15.2.8.5 Trip Computer
Inaccuracy
1. Check fuel sender, ABS /TC CM and ECM signals to instrument pack.
Issue 1 August 1994 X300 EDM 15.2 - 11
