Keep temperature-triggered switching working on cue with the Standard Ignition Diesel Fast Idle Temperature Switch / Engine Coolant Temperature Switch, manufacturer part number TS-621. This thermal switch is factory-calibrated to make electrical contact at its specified temperature set point, delivering the electrical signal its circuit needs based on engine temperature. It installs as a direct-fit replacement for the listed applications — a wide range of 1985-1993 Chevrolet trucks and vans including the Blazer, C10/C20/C30, C1500/C2500/C3500 and C3500HD, G20/G30, and K10/K20/K1500 — spanning L4-3.9L, L6-4.8L, V6-4.3L, V8-5.0L, V8-5.7L, V8-6.2L, V8-6.5L, and V8-7.4L engines; see the Buyer's Guide tab for the full 256-application list.
Listed under both the Diesel Fast Idle Temperature Switch and Engine Coolant Temperature Switch names. Manufacturer part number TS-621 (also TS621). Country of origin: Taiwan.
This part cross-references / interchanges with the following part numbers:
What is the Standard Ignition TS-621?
It is a factory-calibrated thermal switch that makes electrical contact at a specified temperature set point. The catalog lists it under both the Diesel Fast Idle Temperature Switch and Engine Coolant Temperature Switch names.
What vehicles does the TS-621 fit?
It is a direct-fit replacement for many 1985-1993 Chevrolet trucks and vans (Blazer, C10/C20/C30, C1500/C2500/C3500, G20/G30, K10/K20/K1500); see the Buyer's Guide tab for the full 256-application list.
How does this temperature switch work?
It is calibrated to make electrical contact at its specified temperature set point, sending the electrical signal its circuit needs as engine temperature changes. Diagnose the cause of any issue before replacing.
What are signs this switch may need replacing?
Signs the switch may need replacing include no signal or a circuit that switches at the wrong temperature. Confirm the switch is the cause before replacing it, since other components can produce similar symptoms.
How does the TS-621 install and connect?
It bolts on and uses a single round, plug-in male connector with two male blade terminals. Consult the vehicle service information for the correct installation procedure.
WARNING: These products can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
