ECM controlled Volvo relay, Ford fan,

Discussion in 'Electrical Systems' started by ErikNORCAL, Sep 16, 2019.

  1. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Anyone running the Volvo relay and ford lincoln mkviii fan activated by the ecm?

    Wired mine up and the fans aren’t turning on. Basically using the high and low speed wires off the ecm as the trigger wires in place of the bmw temp sensor. My feeble electrical skills are telling me I’m missing something.
     
  2. Gary S

    Gary S Administrator Lifetime Gold Member

    Messages:
    24,009
    Likes Received:
    1,553
    Joined:
    Apr 14, 1999
    Location:
    Bismarck, North Dakota
    You need to determine what the signal is supposed to be. Does it turn on with 12v applied, or does it turn on with ground applied and 12v comes through another path? With solid state relays, the control line doesn't even need to be 12v or ground. It can be any voltage between those two potentials.
     
  3. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Thanks Gary, think that just cleared my head up.
    Looks like 12 v applied as the fan speed is temp activated and ground control.
    For low speed fan, using 4 pin relay: Going to run the “1” trigger on the Volvo relay to 30 pin and the low speed fan wire to 86, switched 12 volts to 85. Ground 87.
     
  4. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Ok so I thought I could bench test and get the fan to come on by grounding pin 86 (removed ground control, the low speed fan wire from the ecm and jumpered a ground). I get 12 volts at the fan plug but the fan is not turning on.
     
  5. SRGN

    SRGN Veteran Member

    Messages:
    681
    Likes Received:
    241
    Joined:
    Feb 20, 2009
    Location:
    Central NJ
    85/86 are relay coil. 30 should get 12V or ground, depending on what you want switched on or off. 87 is the other side of the switched contacts. So power and ground on 85 and 86 turn the relay on, whatever is on 30 will get switched on to 87 when the relay is on. I'm not sure on the circuit logic or I could draw the circuit in paint and post it up.
     
  6. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    36830D45-4A1B-4A1A-AA83-B05790F05B0D.jpeg
     
  7. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Above is how I wired it.
    #1 trigger wire on Volvo relay to pin 30. Switched 12v hot to 85 and the ecm ground control wire (primary fan relay) to 86.
    Grounding 86 makes the relay click and I’m getting 12 volts out at the plug end to the fan. However, I thought that would make the fan run too but it’s not (car not running but key on).
     
  8. Twisted_Metal

    Twisted_Metal Administrator Staff Member Lifetime Gold Member

    Messages:
    29,957
    Likes Received:
    2,715
    Joined:
    Feb 26, 2004
    Location:
    Bloomington, MN
    You're getting 12 volts to the fan and it's not running...
    Does the ground for the fan have a good connection?

    If you're using a 2-speed Ford fan... You only want power to one of the two circuits at any given time.
    Powering both hi and low speed will run it at a mid speed but the fan motor won't last long.
     
  9. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Initially only had the low speed circuit wired up, will have to figure out a way to trigger each later.

    Went ahead and Wired up the high circuit just like above except obviously using the #2 trigger and #2 fan out. Used a jumper and grounded pin 86 (now the high speed ground control) got it to come on a few times but can’t keep it on.

    tested the fan motor. Cut the connections and individually jumped the low and high speed fan plug leads to the battery. Low speed is dead. Hi speed comes on. Left my ground lead plug in place as before so it must be good.

    motor must be toast? Would that also cause the problems of not able to keep the fan running when I had it wired up on #2, high speed?
     
    Last edited: Sep 18, 2019
  10. ErikNORCAL

    ErikNORCAL Veteran Member

    Messages:
    1,173
    Likes Received:
    14
    Joined:
    Aug 6, 2003
    Location:
    now in VA
    Borrowed a set of 4th gen f body dual fans. Using the aforementioned test method for the circuits, the fans activated. Went back and tested the Lincoln fan, high speed works. So the circuit theory is correct.

    Found a recent thread that mentions there are single speed Lincoln fans. Appears that’s what I bought years back since used to run a stand alone pwm controller.

    So the good is I can send the replacement fan motor back as there isn’t anything wrong and the replacement is likely single speed too according to this thread.

    https://www.corvetteforum.com/forum...rm-update-testing-replacement-motor-info.html

    Not sure if Using a 1 speed fan is a good choice (also will have ac circuit wired in)?

    probably run the dual 4th gen fans using the same circuitry.
     

Share This Page