Description
Replace a failing pressure switch with the 2601278. This normally open switch features a 3/8-24 male thread, closes at 35 PSI and opens at 25 PSI, and is designed to prevent compressor damage during low refrigerant conditions. Compatible with R12/R134a refrigerant systems.
Signs You Need a New Pressure Switch
- Air conditioning system fails to activate or cycles intermittently
- Low refrigerant warning or compressor clutch disengagement
- Pressure switch connector corroded or loose
- Compressor runs continuously despite low refrigerant charge
Specifications
| Manufacturer | Freightliner OEM |
|---|---|
| Part Number | 2601278 |
| OEM Number | 085108-00 |
| Part Type | Low Pressure Cutoff Switch |
| Operation | Normally Open |
| Fitting Type | Male 3/8-24 UNF thread |
| Close/Open Pressure | 35 PSI close / 25 PSI open |
| Refrigerant | R12/R134a compatible |
| Connector | 2-spade electrical terminals |
Cross References
This part replaces or is equivalent to the following part numbers:
- OEM equivalents: ABP N83 318014, 318014BSM, 4379-RD4191
- Also known as: 70264650, 72162165-4, 3949309
Applications
This low pressure switch fits Freightliner trucks including:
- Freightliner Business Class M2 (1994–2003)
- Freightliner 100–112V Series
- Freightliner FL50, FL60, FL70 models
- Heavy-duty trucks with male 3/8-24 low pressure port
Verify your engine serial number and refrigeration system configuration before ordering to confirm fitment.









