ok I'm repairing my friends 90 cavalier 4cyl auto.
the fan will not come on. so it's overheating.
the a/c clutch will not engage when she turned it on. so no A/c.
these are why she brought it to me. now the engine wiring was a jerry rigged disaster so i replaced it all with a better harness that i checked out before i installed everything in the harness is fine and now installed. it's easier to work with decent wiring so your not fighting 2 problems.
there is also a brand new coolant temp sensor.
and jumping the relay will turn on the fan
and still the fan will not come on if i leave the car running in the garage, and the a/c isn't working. whats going on with this car????????
I've tested the relay just now and with the coil on and off it sends power where it's supposed to go. now it could be an internal high amperage short in the relay.
but for the most part i don't think the relay is getting signal to turn on
I had the same problem on my sunbird but I didn't want to spend the money on getting a tech to find the problem. So I wired my own manual fan switch to stop the overheating. It's very easy to do and it cost basically nothing, like 5 bucks. Theres a how to on v6z24.com telling you which wire in the relay to ground for the switch.
If you find the problem, let me know tho. It would be good to have the car working like it should be
2003 Cavalier 2dr. 5spd
1. The 25 amp Heater/AC fuse supplies +12 volts to Terminal 86 of the relay Base(Socket)----this is one connection of the relay energising coil.
2. Terminal 85 is the other end of the relay coil, this is energised (Grounded) by the E.C.M. pinC13 and is a Dark Green/White wire. This is grounded when the temperature of the coolant reaches 105 Centigrade/221 deg F It is then switched off/Ungriunded at 99 deg C/ 210F
3. (Hot when Battery connected) Fusible link C (RED) from Starter motor "Bat" terminal supplies +12 volts to Terminal 30, to run the Cooling Fan when the E.C.M. switches On the relay.
4..Terminal 87 is supplied from Terminal 30 when the relay is energised.
[I've tested the relay just now and with the coil on and off it sends power where it's supposed to go] [and jumping the relay will turn on the fan]
You seem to have everything there except the Dark Green/White wire from the E.C.M. is not grounding the relay when the temp is reached.
If the coolant is up to the 221 deg F temp, remove the Cooling fan relay, connect one wire of a test lamp to +12 volts and the other to Relay Base/socket Pin 85. The test lamp should illuminate if the E.C.M. is providing the ground and the Dark Green/White wiring is correct.
The A/c clutch will not engage if the A/C pressure sensor sees less than 44 p.s.i.
Alont
Barring the miswire disaster, the fan won't normally come on if the A/C pressure isn't up to snuff. Short of refurbishing your whole A/C system (which I did for a ton of money!), follow the advice to install a switch to kick the fan on. (I did the same on my '84 Sunbird Turbo.....)
Take care,
Moe
The fan will operate to cool the radiator whether the A/C is operational or not.
(Both my ,93 2.2's have had A/C systems inoperative for years, yet the Cooling Fans will come on if the temperature goes above normal--esp in slow traffic/hot weather)
The fan will operate to cool the radiator whether the A/C is operational or not.
(Both my ,93 2.2's have had A/C systems inoperative for years, yet the Cooling Fans will come on if the temperature goes above normal--esp in slow traffic/hot weather)
1. If the coolant temperature rises above the limit (221-223 deg F)
2.Diagnostic Trouble Code (DTC) 14 is set.[Coolant temp over 275 deg F for 1 sec]
3. A/C pressure is 51 p.s.i. or greater with A/C selected and DTC 66 NOT set. [DTC 66 is set when A/C pressure sensor readings fall outside of the normal possible range of the sensor--and not due to a refrigerant system problem.
NOTE If the A/C is selected and the system is operational (Pressure correct) the Cooling Fan will run whilst the A/C is selected.
scott (section8cav) wrote:
{ok..i dont know why he bought you an extra relay..sounds like you need to throw all that out...}---disregard this
if you look in your engine bay there is a black fuse box on the driver side..one of the big relays will be labeled "cooling fan" ...pull that box up and look under it...if you look under the relay on the bottom of the box there should be 4 wires ...3 thick ones and 1 small one..the really small one is a green or light blue color iirc[Dark Green/White in mine--Alont] .. just splice into /dont cut/ that wire ..run it to the cabin, hook it to a switch,then run the switch to ground..its that easy...now, when ever the switch is ON the fan will come on..whenever the switch is OFF the fan will work just like its supposed to..cus all your doing is grounding the relay to the fan and making it come on when you hit the switch
Alont
with the engine running, does the fan kick on a few seconds after unplugging the temp sensor(located at the upper rad hose water neck on the back of the engine just above the trans bellhousing?)
it should
it is supposed to anyways
good luck
-96 cavalier 2.2 auto 143k miles
