Description
Vehicle Compatibility & OE Cross Reference
Alternator voltage regulator for Bosch alternators on select Toyota applications where the original regulator matches an A Circuit design with IR/IF internal regulator internal fan configuration and a 4 pin connector in the IG S L DFM or IG S L FR layout. Confirm by alternator label, plug format and OE cross reference.
OE Numbers By Brand
- Toyota: 27700-0L020
Application Note
Referenced as Bosch 4 pin Toyota regulator for KCB1 and E4 alternator applications where the original regulator uses the same 4 pin IG S L DFM or IG S L FR configuration.
Specifications
- Reference: REG1075
- Part Type: Alternator Voltage Regulator
- Manufacturer: Bosch
- System Voltage: 12V
- Regulated Voltage (Set Point): 14.4V (VS=14.4V)
- Charging Voltage: 14.4V
- Operating Voltage: 14V
- Circuit: A Circuit
- Type: IR/IF (Internal Regulator / Internal Fan)
- Connector / Pins: 4 Pin IG S L DFM / 4 Pin IG S L FR
- Plug Type: IDIG Sense L CPU
- Specification: 5 Sec. LRC
- Active Lamp: Yes
- Short Circuit Protection: Yes
- OE Number: Toyota 27700-0L020
Features
- Regulates alternator field current to maintain stable charging on compatible Bosch Toyota alternators
- 14.4V charging specification for matching 12V electrical systems
- 4 pin IG S L DFM or IG S L FR connection with IDIG Sense L CPU plug type
- A Circuit control strategy and IR/IF internal regulator internal fan configuration for specified alternator designs
- 5 sec LRC specification with active lamp function and short circuit protection
Why Buy From Us
- Local South African stock with nationwide courier delivery
- 12-month warranty subject to correct application and installation
- Fitment support using alternator labels, plug photos and OE number matching
- Trusted by workshops and DIY customers for reliable charging system components
Trusted by thousands of South African drivers for quality and durability.
Installation & Maintenance Tips
- Disconnect the battery before alternator removal or regulator replacement
- Match the regulator by Bosch manufacturer, A Circuit design and the 4 pin IG S L DFM or IG S L FR plug layout
- Inspect brushes, slip rings and rotor condition while the alternator is open and replace worn parts where required
- Ensure battery terminals and earth connections are clean and tight to prevent voltage drop
- After installation, verify charging voltage at idle and under load and confirm warning lamp behaviour
- If you are unsure about alternator repairs, have the regulator fitted and tested by a qualified auto electrician