5 minute cooling mod (Always on IC pump)
#1
Junior Member
Thread Starter
5 minute cooling mod (Always on IC pump)
Discovered this quick and easy cooling mod after doing a bit of research into the pump the car is equipped with. Turns out that you only need to disconnect the PWM signal to the pump in order to switch it to a max power / always on mode. Common mod on any air to water intercooler equipped cars, so I was surprised that nobody has discovered it. Goes to show the sad state of M276 modding I guess, wish we got more "easy" mods for these cars like my C32 and CL55, which had tons of easy mods to make the cars better. Anyways, I did notice that the temps recover much quicker with the mod and IAT's sit a bit lower than before, also might help a bit with temp recovery after a race or sitting in staging lanes. Not going to make a massive difference but it is noticeable for me and your car will be happier with it.
Posted the video below but really all you need to do is "disconnect" the black and yellow wire going to your intercooler pump, which is behind the passenger side bumper grill accessible from underneath after removing the skid trays. You can make a simple harness using connectors if you want to go back to factory whenever you want, and you could make it even better and put a switch between the black wires to go back to OEM whenever you flip the switch but I decided not to as I want the cooling at all times and the pumps are cheap so I don't care about longevity. This sets the pump to an on/off mode, and the car already supplies switched 12v power to the pump with the key in accessory so the pump will turn on and run at full power. Have not thrown any codes for a week and 600 miles of driving (and a few races in Mexico). Video has more info.
Posted the video below but really all you need to do is "disconnect" the black and yellow wire going to your intercooler pump, which is behind the passenger side bumper grill accessible from underneath after removing the skid trays. You can make a simple harness using connectors if you want to go back to factory whenever you want, and you could make it even better and put a switch between the black wires to go back to OEM whenever you flip the switch but I decided not to as I want the cooling at all times and the pumps are cheap so I don't care about longevity. This sets the pump to an on/off mode, and the car already supplies switched 12v power to the pump with the key in accessory so the pump will turn on and run at full power. Have not thrown any codes for a week and 600 miles of driving (and a few races in Mexico). Video has more info.
The following 3 users liked this post by Ginco:
#3
Junior Member
Thread Starter
#4
Senior Member
Curious how long the pump lasts like that. Would be nice to have an in car switch for this. Id guess they went with pulse width to extend pump life and to help with noise at idle/ acc on.
Would also be curious what the signal looks like during normal driving. Id assume its modulated based on IAT and load.
Would also be curious what the signal looks like during normal driving. Id assume its modulated based on IAT and load.
#5
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
Discovered this quick and easy cooling mod after doing a bit of research into the pump the car is equipped with. Turns out that you only need to disconnect the PWM signal to the pump in order to switch it to a max power / always on mode. Common mod on any air to water intercooler equipped cars, so I was surprised that nobody has discovered it. Goes to show the sad state of M276 modding I guess, wish we got more "easy" mods for these cars like my C32 and CL55, which had tons of easy mods to make the cars better. Anyways, I did notice that the temps recover much quicker with the mod and IAT's sit a bit lower than before, also might help a bit with temp recovery after a race or sitting in staging lanes. Not going to make a massive difference but it is noticeable for me and your car will be happier with it.
Posted the video below but really all you need to do is "disconnect" the black and yellow wire going to your intercooler pump, which is behind the passenger side bumper grill accessible from underneath after removing the skid trays. You can make a simple harness using connectors if you want to go back to factory whenever you want, and you could make it even better and put a switch between the black wires to go back to OEM whenever you flip the switch but I decided not to as I want the cooling at all times and the pumps are cheap so I don't care about longevity. This sets the pump to an on/off mode, and the car already supplies switched 12v power to the pump with the key in accessory so the pump will turn on and run at full power. Have not thrown any codes for a week and 600 miles of driving (and a few races in Mexico). Video has more info.
https://youtu.be/wy0VuvUHSsI
Posted the video below but really all you need to do is "disconnect" the black and yellow wire going to your intercooler pump, which is behind the passenger side bumper grill accessible from underneath after removing the skid trays. You can make a simple harness using connectors if you want to go back to factory whenever you want, and you could make it even better and put a switch between the black wires to go back to OEM whenever you flip the switch but I decided not to as I want the cooling at all times and the pumps are cheap so I don't care about longevity. This sets the pump to an on/off mode, and the car already supplies switched 12v power to the pump with the key in accessory so the pump will turn on and run at full power. Have not thrown any codes for a week and 600 miles of driving (and a few races in Mexico). Video has more info.
https://youtu.be/wy0VuvUHSsI
#6
Member
After seeing this today I wanted to check it out. Found the pump by removing 3 plastic rivets from the wheel well. I could not get the plug off and didnt want to cut the wire without an easy way to reconnect it should I need to. I followed the wires and found they come up and into the battery compartment. Remove the cover and its the bundle of wire closest to the motor. Strip back the tape, cut and insulate the black/yellow wire, retape the bundle. There is only one Black/Yellow wire in there. I cut that one and then turned the ignition on and the pump went full speed and works as shown above.
Thanks OP for the video!
Thanks OP for the video!
The following 2 users liked this post by Adam Chambers:
Ginco (06-05-2023),
jonathan358 (06-06-2023)
#7
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
After seeing this today I wanted to check it out. Found the pump by removing 3 plastic rivets from the wheel well. I could not get the plug off and didnt want to cut the wire without an easy way to reconnect it should I need to. I followed the wires and found they come up and into the battery compartment. Remove the cover and its the bundle of wire closest to the motor. Strip back the tape, cut and insulate the black/yellow wire, retape the bundle. There is only one Black/Yellow wire in there. I cut that one and then turned the ignition on and the pump went full speed and works as shown above.
Thanks OP for the video!
Thanks OP for the video!
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#8
Member
2016 C450. From other posts I have seen, the face lift cars are easy too as the relay is right next to the reservoir.
#9
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
#11
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#12
After seeing this today I wanted to check it out. Found the pump by removing 3 plastic rivets from the wheel well. I could not get the plug off and didnt want to cut the wire without an easy way to reconnect it should I need to. I followed the wires and found they come up and into the battery compartment. Remove the cover and its the bundle of wire closest to the motor. Strip back the tape, cut and insulate the black/yellow wire, retape the bundle. There is only one Black/Yellow wire in there. I cut that one and then turned the ignition on and the pump went full speed and works as shown above.
Thanks OP for the video!
Thanks OP for the video!
Thanks to OP and to you for the shortest way!!
#14
Junior Member
Thread Starter
After seeing this today I wanted to check it out. Found the pump by removing 3 plastic rivets from the wheel well. I could not get the plug off and didnt want to cut the wire without an easy way to reconnect it should I need to. I followed the wires and found they come up and into the battery compartment. Remove the cover and its the bundle of wire closest to the motor. Strip back the tape, cut and insulate the black/yellow wire, retape the bundle. There is only one Black/Yellow wire in there. I cut that one and then turned the ignition on and the pump went full speed and works as shown above.
Thanks OP for the video!
Thanks OP for the video!
#16
Junior Member
Thread Starter
Curious how long the pump lasts like that. Would be nice to have an in car switch for this. Id guess they went with pulse width to extend pump life and to help with noise at idle/ acc on.
Would also be curious what the signal looks like during normal driving. Id assume its modulated based on IAT and load.
Would also be curious what the signal looks like during normal driving. Id assume its modulated based on IAT and load.
#17
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
So is idling louder now?
#19
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
#20
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PFL205.064 with M276.823 (Oil pump solenoid defeated)
After seeing this today I wanted to check it out. Found the pump by removing 3 plastic rivets from the wheel well. I could not get the plug off and didnt want to cut the wire without an easy way to reconnect it should I need to. I followed the wires and found they come up and into the battery compartment. Remove the cover and its the bundle of wire closest to the motor. Strip back the tape, cut and insulate the black/yellow wire, retape the bundle. There is only one Black/Yellow wire in there. I cut that one and then turned the ignition on and the pump went full speed and works as shown above.
Thanks OP for the video!
Thanks OP for the video!
#22
#23
Super Member
Great find, thanks @Ginco for the mod and @Adam Chambers for the shortcut!
#25
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PFL205.064 with M276.823 (Oil pump solenoid defeated)