Head Gasket and head repair

[hungryhound69]

The 50% fan turns on if a/c is on, no matter the temperature of the coolant. And it would stay on at 50% but after it gets to above 90C, not straight away it has to stay there for a while I would get the active status on low speed relay and 58% on fan demand but 0% on the fan, but sometimes the fan is running sometimes it isn't. Tapping on the control module (1267j4) or wiggling the wires makes no difference. Eventually after 10-15 seconds the high speed fan would turn on if the slow fan isn't running. But while it gets active status on high speed and 100% on fan demand the fan speed continues to show 0% for 10-15 seconds or there about. And each time this happens and it seems a rare event I get the P0485 code. This morning I tried to recreate it and it took a long time as it's about 9C outside while yesterday it was around 16C in the afternoon so it happen sooner. Monitoring with LEXIA is too bulky while driving so I have a Bluetooth dongle to monitor through my phone. But the events are quite consistent. What is puzzling is that sometimes when the fan is clearly spinning it shows 0% for the fan. I'm wondering it it's the control module, but if it was a stuck relay then tapping it should do something.

[ozvtr]

It sounds like it's the module.
There might not be any relays in the module. The fans could be run by transistors.

[hungryhound69]

If you pull up the schematic it shows relays. In any case I swapped it for a cheap Chinese unit I bought off amazon for 17EUR and lo and behold the weird behaviour vanished. I drove the car for over an hour and then today through the city stopping and parking so the temperature went up to 105C when a slow fan kicked in. Otherwise no error codes or phantom fans. So it was the control unit So I ordered a MOPAR unit since I don't trust the cheap Chinese one.