LS587
New Member
- Thread starter
- #1
This is mostly for information, but I would be interested to know how many others have had their pump fail. After 3 weekends of trying to figure out if mine had failed, I have confirmed that it clearly is failed on my 2016 Track Pack. The car has 2900 miles on it, and most of those are track miles, because I hardly drive it on the street and it goes to the track in a trailer.
2 summers ago at Road America, we noticed a slight smell of differential oil, and when back home, found that some oil had pushed out of the differential breather tube vent in the right rear wheel well. I extended the tube into the trunk where I placed a small vent tank, and after draining the differential, refilled it with 75W140, instead of Ford's recommended 75W90 that I had been using. Last summer at Road America, there was no fluid smell, and no oil in the vent can.
However, I was suspicious about the pump, so I read everything that I could find on this forum about checking the differential pump.
I got Forscan and finally figured out how to trigger the pump on and off. However, I could only get it to run about a second and stop. I did things like aimed two 500 watt heat lamps at the differential case to warm the oil up to 160 degrees F, and even pulling the temperature sensor out (thanks to this forum for informing me that it doesn't seal oil) and heating it up to 290+ degrees F with a heat shrink gun.
Thanks to someone who posted a Ford circuit diagram, I tried my best to troubleshoot the power, ground and signals to the 6-pin connector on the pump. I finally got to the point, by measuring wire voltages by inserting straight pins to pierce into the wires, that pins 1 and 2 always had 12 volts on them, pin 6 was ground, and when I activated the pump with Forscan, the SPEED CONTROL line went up from less than a volt to about 10 volts, and stayed there after the pump quit running, only going to a low voltage when I clicked OFF in Forscan.
At that point, I was convinced that something was wrong with the pump. Just to see what I could find, I removed the plastic cover that has the 6-pin socket on the pump, and found a sophisticated control board on the back of it. I attached a photo for those who have not seen it. It looked generally OK, other than near the power pins that connect to the motor, there was an odd whitish color on the circuit board, possibly indicating high heat in that area. It must be a brushless DC motor that requires electronics to control the motor.
I put the circuit board back on the pump and disconnected the pump outlet line, in case it or the cooler was plugged. When the pump was run for its approximately 1 second duration, no oil came out, even with successive ON cycles. I disconnected the pump inlet line, and got the same result. I blew some air backwards through the pump, in case something got caught in it. Again no success.
I finally decided to disassemble the pump, by removing the motor with the pumping element from the inlet/outlet housing. I found a nice little gerotor pump that would spin freely. I attached a photo looking at the end of it. When I would actuate the pump with Forscan, the motor shaft would just wiggle back and forth a few degrees for about a second and then stop. I even pulled the center pump element out with a magnet, so that the pump shaft had nothing on it, and saw the same result.
I conclude that the pump's circuit board probably senses a fault and stops powering it and possibly triggers a fault signal. The DIAG line (pin 5) does change voltage when I actuate the pump and when the pump stops. I believe it was about 1.8 volt with the pump command off, went up to about 3.2 when the motor was trying to run and dropped to about 2.2 when the motor stopped.
I've ordered a new pump, and when I get it back together, I'll see if I can determine at what oil (differential cover) temperature the pump turns on, because from what I found on this forum, Ford doesn't tell us what that is. It is known that a fault signal will be set when the oil reaches 145 degrees C, which is 293 degrees F, and I believe that I set a fault signal when I got the temperature sensor up to 295 degrees F.
2 summers ago at Road America, we noticed a slight smell of differential oil, and when back home, found that some oil had pushed out of the differential breather tube vent in the right rear wheel well. I extended the tube into the trunk where I placed a small vent tank, and after draining the differential, refilled it with 75W140, instead of Ford's recommended 75W90 that I had been using. Last summer at Road America, there was no fluid smell, and no oil in the vent can.
However, I was suspicious about the pump, so I read everything that I could find on this forum about checking the differential pump.
I got Forscan and finally figured out how to trigger the pump on and off. However, I could only get it to run about a second and stop. I did things like aimed two 500 watt heat lamps at the differential case to warm the oil up to 160 degrees F, and even pulling the temperature sensor out (thanks to this forum for informing me that it doesn't seal oil) and heating it up to 290+ degrees F with a heat shrink gun.
Thanks to someone who posted a Ford circuit diagram, I tried my best to troubleshoot the power, ground and signals to the 6-pin connector on the pump. I finally got to the point, by measuring wire voltages by inserting straight pins to pierce into the wires, that pins 1 and 2 always had 12 volts on them, pin 6 was ground, and when I activated the pump with Forscan, the SPEED CONTROL line went up from less than a volt to about 10 volts, and stayed there after the pump quit running, only going to a low voltage when I clicked OFF in Forscan.
At that point, I was convinced that something was wrong with the pump. Just to see what I could find, I removed the plastic cover that has the 6-pin socket on the pump, and found a sophisticated control board on the back of it. I attached a photo for those who have not seen it. It looked generally OK, other than near the power pins that connect to the motor, there was an odd whitish color on the circuit board, possibly indicating high heat in that area. It must be a brushless DC motor that requires electronics to control the motor.
I put the circuit board back on the pump and disconnected the pump outlet line, in case it or the cooler was plugged. When the pump was run for its approximately 1 second duration, no oil came out, even with successive ON cycles. I disconnected the pump inlet line, and got the same result. I blew some air backwards through the pump, in case something got caught in it. Again no success.
I finally decided to disassemble the pump, by removing the motor with the pumping element from the inlet/outlet housing. I found a nice little gerotor pump that would spin freely. I attached a photo looking at the end of it. When I would actuate the pump with Forscan, the motor shaft would just wiggle back and forth a few degrees for about a second and then stop. I even pulled the center pump element out with a magnet, so that the pump shaft had nothing on it, and saw the same result.
I conclude that the pump's circuit board probably senses a fault and stops powering it and possibly triggers a fault signal. The DIAG line (pin 5) does change voltage when I actuate the pump and when the pump stops. I believe it was about 1.8 volt with the pump command off, went up to about 3.2 when the motor was trying to run and dropped to about 2.2 when the motor stopped.
I've ordered a new pump, and when I get it back together, I'll see if I can determine at what oil (differential cover) temperature the pump turns on, because from what I found on this forum, Ford doesn't tell us what that is. It is known that a fault signal will be set when the oil reaches 145 degrees C, which is 293 degrees F, and I believe that I set a fault signal when I got the temperature sensor up to 295 degrees F.
Sponsored
