Starting and charging – circuit operation
- Make
- Land Rover
- Model
- Discovery Electrical Troubleshooting Manual
- Year
- 1997 on
- Section
- Circuit operation › Starting and charging – circuit operation
STARTING AND CHARGING – CIRCUIT OPERATION
B1 STARTING AND CHARGING
Starting System (MFI-T16) (300 Tdi with EGR) (300 Tdi with EDC) Putting the Ignition Switch (X134) in position lll applies battery voltage to the Starter Solenoid Relay’s (K137) terminal 85. With the vehicle in Park or Neutral (Automatic only) and/or the Theft Alarm de—activated, the Starter Solenoid Relay (K137) energises. Battery voltage is then applied directly to the Starter Solenoid (K136) and the Starter (M134).
On manual transmission vehicles equipped with a theft alarm, the Theft Alarm Unit (Z163) provides a ground circuit to the Starter Solenoid Relay’s (K137) 86 terminal.
On automatic transmission vehicles equipped with a theft alarm, the Theft Alarm Unit (Z163) provides a ground circuit to the Starter Solenoid Relay’s (K137) 86 terminal via the Park/Neutral Position Switch (X167).
If the theft alarm is activated, the Theft Alarm Unit (2163) will interrupt the Starter Solenoid Relay’s (K137) ground path. The Starter Solenoid Relay (K137) will remain de—energised and prevent starting the engine.
For vehicles not equipped with Theft Alarm, a black wire is used to short pins 10 and 11 of C274.
Charging System When the Ignition Switch (X134) is in position II, battery voltage is applied to the charging system fault light. When the Generator (Z106) is being turned by the engine, its stator windings are excited by voltage applied to the Generator (Z106) via the charging system fault light. The Generator (Z106) begins to produce electricity in order to charge the vehicle Battery (P104). If the Generator (Z106) fails to produce power, the Generator (Z106) grounds the fault light control wire, causing the charging system fault light to glow.
The tachometer displays engine speed in rpm. Voltage pulses are taken from the Generator (Z106) and are generated when the engine drive belt turns the Generator pulley. The tachometer responds to the frequency of the voltage pulses, which increases proportionally to that of the engine speed.
2 CIRCUIT OPERATION
Parts & tools for this job For 1997 Land Rover Discovery
- TOOLBattery testerSearch: car battery tester
- TOOLDigital multimeterSearch: automotive digital multimeter
- TOOLBattery terminal cleanerSearch: battery terminal cleaner
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