Question about Chevrolet Cars & Trucks
The van over heats and fan not working
There are two fuses in the under hood fuse / relay box. cool fan 1 and cool fan 2 , both are 30 amp. test these first . There are also three relays which are given a ground by the PCM .
The engine cooling fan system consists of 2 electrical cooling fans and 3 fan relays. The relays are arranged in a series/parallel configuration that allows the powertrain control module (PCM) to operate both fans together at low or high speeds. The cooling fans and fan relays receive battery positive voltage from the underhood junction block. The ground path is provided at G117.
During low speed operation, the PCM supplies the ground path for the low speed fan relay through the low speed cooling fan relay control circuit. This energizes the cooling fan 1 relay coil, closes the relay contacts, and supplies battery positive voltage from the cool fan 1 maxifuse® through the cooling fan motor supply voltage circuit to the left cooling fan. The ground path for the left cooling fan is through the cooling fan relay and the right cooling fan. The result is a series circuit with both fans running at low speed.
During high speed operation the PCM supplies the ground path for the cooling fan 1 relay through the low speed cooling fan relay control circuit. After a 3-second delay, the PCM supplies a ground path for the cooling fan 2 relay and the cooling fan relay through the high speed cooling fan relay control circuit. This energizes the cooling fan relay coil, closes the relay contacts, and provides a ground path for the left cooling fan. At the same time the cooling fan 2 relay coil is energized closing the relay contacts and provides battery positive voltage from the cool fan 2 maxifuse® on the cooling fan motor supply voltage circuit to the right cooling fan. During high speed fan operation, both engine cooling fans have there own ground path. The result is a parallel circuit with both fans running at high speed.
It would help if you had access to scan tool with bidirectional control to see if you could turn them on that way. you could jump power directly to fan's to see if they work.How to test relay
VEHICLE RELAYS Operation Diagnosis
Posted on Dec 14, 2014
Are you talking about the radiator fan? How hot does the engine get in degrees F? Some makes and models, the radiator fan won't turn on till about 220 degrees F. Check for applicable trouble codes, see if any code that refers to the radiator fan circuit or coolant temp sensor? Some of the national brand auto stores will check codes for free.
Of course, as far as overheating in general, you have the thermostat--water pump and other possible issues. Are you losing coolant?
Posted on Dec 14, 2014
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
May 01, 2017 | 2001 Chevrolet Venture
Aug 30, 2011 | 2004 Chevrolet Venture Passanger
Oct 03, 2010 | 2004 Chevrolet Venture
Jan 17, 2010 | 1999 Chevrolet Venture
Nov 12, 2009 | 1997 Chevrolet Venture
Jun 10, 2009 | 2004 Chevrolet Venture Passanger
May 31, 2009 | 2004 Chevrolet Venture Passanger
296 people viewed this question
Usually answered in minutes!