Adding a manual fan switch??

[JMBT]

Hello, has anyone posted a thread on adding a manual fan switch? I have a 2012 Volvo with a Cummins 2250, and would like to add one. If I manipulate the signal wires at the fan's air solenoid, to cut out the 12V signal sent from the ECM, will I throw a fault code?? Thanks in advance for any info, or direction to another thread on this subject.

[Rawze]

(02-14-2017 )JMBT Wrote:  Hello, has anyone posted a thread on adding a manual fan switch? I have a 2012 Volvo with a Cummins 2250, and would like to add one. If I manipulate the signal wires at the fan's air solenoid, to cut out the 12V signal sent from the ECM, will I throw a fault code?? Thanks in advance for any info, or direction to another thread on this subject.

YES, the ecm throws a fault if you interrupt the circuit.

I have sen guys get a second fan solenoid and plum it in to control it so that there is no faults.

[mmssvv]

Yes!I did exactly what Rawze said.
I installed some 12V IngersollRand solenoid and used one of AUX switch on the dash which has wires outlet under the hood to power it.Four Years, no problem.
If you need the part number on this solenoid, I can try to find for you.
Remember-The solenoid must have three air ports.In,One normally Open and one Normally Closed.
This is necessary,because the remaining pressure between fan clutch and solenoid must be exhausted after solenoid is activated.

[Magard]

Lowering fan cut in temperature seems to be a good thing also. So far I don't see any negatives. Oil temps run cooler. Seem to follow right with the new cut in temp. Lowered cut in temp 10 degrees oil runs 10 degrees cooler, after oil thermostat temperature is reached.

[JMBT]

Thank you all for the info. That's what I was afraid of. I sure don't need any more reasons to throw fault codes.
mmssvv, if the part number isn't too hard for you to find, I would appreciate it, but if it's a pain in the ass, no worries, i'm sure i can find something.
I have heard if I can find the corresponding pin on the Volvo OEM harness at the ECM, I can switch it through the ECM. Then enable manual fan mode with insite and get no codes, but I cannot find a pinout diagram for the Volvo OEM to Cummins ECM connector. If any of you know where to find that please let me know. If not I will end up going with the second solenoid idea.
Magard, I like that idea too.

[snailexpress]

(02-15-2017 )JMBT Wrote:  Thank you all for the info. That's what I was afraid of. I sure don't need any more reasons to throw fault codes.
mmssvv, if the part number isn't too hard for you to find, I would appreciate it, but if it's a pain in the ass, no worries, i'm sure i can find something.
I have heard if I can find the corresponding pin on the Volvo OEM harness at the ECM, I can switch it through the ECM. Then enable manual fan mode with insite and get no codes, but I cannot find a pinout diagram for the Volvo OEM to Cummins ECM connector. If any of you know where to find that please let me know. If not I will end up going with the second solenoid idea.
Magard, I like that idea too.

Easiest way to add manual switch. Check the VECU under dash. If green connector has pin on PA19 just connect it to the FAN MANUAL switch. If no wire coming out from PA19 cavity you have to buy terminal P/N for the Volvo terminal 3948725 to install at the location PA 19 of the big green connector on the VECU, also no parameter need to be change to run the manual fan option

[JMBT]

snailexpress, thanks for the reply, I read about this, but was told it would only work with a Volvo motor and with the cummins motor I had to go through the ECM?? Have you done this mod on a volvo truck with a cummins motor?

[snailexpress]

(02-15-2017 )JMBT Wrote:  snailexpress, thanks for the reply, I read about this, but was told it would only work with a Volvo motor and with the cummins motor I had to go through the ECM?? Have you done this mod on a volvo truck with a cummins motor?

I did it on my 2009 Volvo I had. Cummins engine is under VECU control same as Volvo engine. No difference. Everything is going thru 1939

[JMBT]

snailexpress, So you had no fault codes from the Cummins side when you did this on your truck with a cummins motor? That does makes sense, all is under VECU control. I really appreciate the info! I will check to see if my green connector has PA19 pin.