1996 pontiac grand prix wiring?

Question

my 96 gp 3100 has fans that are not working. if im when the temp sending unit reaches the right temp it sends a signal to the fan control relay. or does it send a signal to the ecm which then sends a signal to fan control relay. and does if i remember right it sends the relay a ground signal. because there is always a hot to it. what all could be the problem. i have constant power. my fans work when they are hot wired. and i dont want to set up a toggle swich. wiring is my hardest subject but is the best task to overcome. what could be the problem

Answer 1

If your system has single Temp switch



Reading temp is picked up by sensor/switch

runs back to Gauge

gauge runs to and though Ignition switch

to ECM to Fan Relay

to FAN



Relay has power supply from Fusible link and ECM



I still haven't found a wiring diagram for your model...



If gives off 225 temp reading when cool and has a New sensor has a short somewhere. or bad part or connection.



If running and just rises quickly and motor gets hot just as quick you might have 2 problems.



Also if yours system has 2 temp sensors completely differ



Parts list

Temp sensor

fan relay

relay Fuseable link

Gauge

printed circuit

ignition switch

ECM

shorts off ECM

(( low Coolant module runs wire back to ecm ))

Service engine soon through printed circut

Answer 2

ECM first, but what about AFTER a coolant temp sensor? Then to relay, ground signal sounds reasonable and correct, with hot present. Replace temp sending unit!

Answer 3

relay is good? may go through the ecm, could send the signal from the temp switch, to the relay, relay coil, or contacts bad?