jb1

I really could use some help, Im in the process of changing the radiator/hoses/thermostat etc. I bought a new CTS and changed that, but saw this other sensor to the left of it. It has BOSCH stamped on it, 35*c and 12v...is this the fan control sensor?....thought it should be on pass side block?

I have a GM service manual, however it didnt show location on the diagram.

86 camaro IROC 305 TPI/Auto

The sensor in question is on the left in all pics.

jb1

is this the cold start injector thermo-time switch?

do they still sell these?

vetteoz

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But you will need your credit card

jb1

thanks, Im realy wanting to delete this with the block off plates and program....in the meantime....is there a way to test this sensor?.....resistenace?

Im just trying to get this bolted back up now.

Vader

It's the cold start thermo switch. It contains a heat element, bimetallic contacts, and the coolant capsule. The contacts should be closed below 90° (opens at about 95°) so that only the primary heat element resistance is in the circuit. The B terminal (tan wire) should have about 0.5 ohms to the grounded case when cold. The A terminal (purple wire) should read about 35 ohms to ground. Once heated, the B terminal should open until the temperature drops below 90°.

jb1

Thanks, it measures .4 ohms and 35 ohms respectively from connector blade to sensor tip, when heated with my heat gun the .4ohms moves to 146 ohms and the 35 ohms moves to 72 ohms.

should I assume this switch is good?

Mancha87

Does that switch control my fan by any chance? its not turning on and I've already replaced cts,fan motor and fan relay....