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PRC4427 - Voltage Sensitive Switch – 45A

Original price - Original price €170,00
Original price
€170,00
€170,00 - €170,00
Current price €170,00
Genuine Part
Genuine: Original manufacturer part. This product is the original part designed and produced by the vehicle manufacturer.
Voltage Sensitive Switch - a 45-amp voltage-sensitive relay used in the vehicle's auxiliary charging and accessory circuits.

The switch monitors system voltage and closes its main contacts once the sensed voltage rises above its threshold, bringing a secondary circuit online only while the charging system is active. It is used to control the split-charge circuit, the heated rear window supply and the air-conditioning relay circuit, switching the high-current load on the strength of the monitored voltage rather than a manual feed.
Vehicle Model Land Rover Defender up to 2016
Land Rover Discovery 1 1989-1998 (L318)
Range Rover Classic up to 1994
Fitment Notes DEFENDER 1987-2006 — 45 AMP voltage sensitive switch; Heated Rear Window circuit and Split Charge circuit (VIN DA310169-MA962814)
DISCOVERY 1 1989-1998 — 45 AMP, switch volt sensitive
RANGE ROVER CLASSIC 1986-1991 — 45 AMP, voltage sensitive switch; Air Conditioning relay circuit
RANGE ROVER CLASSIC 1992-1994 — 45 AMP, voltage sensitive switch; LHD and RHD variants (VIN JA610294-JA624780)
Alternative Codes
PRC4427

In stock 1 unit
1 · Gouda 0 · Drachten
Express delivery available

When will my order arrive?
  • Order before 15:00 (Mon–Fri): same-day dispatch for in-stock items.
  • UPS Express (order before 14:00): dispatched today, delivered tomorrow where available.
  • Netherlands / Belgium / Germany: 2–4 working days.
  • Other EU countries + UK: 4–8 working days.
  • Outside EU/UK: delivery times vary — contact us for an estimate.

Items may ship from multiple warehouses at no extra cost.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What does the PRC4427 voltage sensitive switch do?
The PRC4427 is a 45-amp voltage-sensitive switch that closes a high-current circuit once system voltage rises above its threshold. It brings a secondary load online only while the charging system is active, switching on monitored voltage rather than a manual feed.
Which circuits does the 45A voltage sensitive switch control?
The 45A voltage sensitive switch controls the split-charge and heated rear window circuits on the Defender, and the air conditioning relay circuit on Range Rover Classic. It energises these high-current loads when the charging system raises system voltage.
Which Land Rover models does the PRC4427 fit?
The PRC4427 fits the Defender 1987-2006 (VIN DA310169 to MA962814), Discovery 1 1989-1998 and Range Rover Classic up to 1994. Check your VIN against the chassis ranges, as Range Rover Classic 1992-1994 covers VIN JA610294 to JA624780.
How many voltage sensitive switches are needed?
Typically one voltage sensitive switch is fitted per controlled circuit. A vehicle usually needs a single PRC4427 for its split-charge or heated rear window supply, though setups running several auxiliary circuits may use more than one.