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No
that code says that the cooling fan 2 circuit has a failure, when it tried to turn it on the computer did not see a voltage change thus your code. Check the cooling fan 2 relay.
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DTC P0128 Engine Coolant Temperature (ECT) Below Thermostat Regulations Temperature
An engine coolant temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the powertrain control module (PCM) for engine control and as an enabling criteria for some diagnostics.
The air flow coming into the engine is accumulated and used to determine if the vehicle has been driven within the conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not increase normally or does not reach the regulating temperature of the thermostat, the diagnostics that use ECT as enabling criteria may not run when expected.
If the PCM detects the calibrated amount of air flow and engine run time have been met, and the ECT has not met the minimum thermostat regulating temperature, DTC P0128 sets.
P0481
Cooling Fan Relay 2 Control Circuit
PCM
DTC P0480 or P0481
Have you changed the thermostat ?
Do you know how to test cooling fan relay (S)
Battery positive voltage is supplied to the cooling fan 1 relay from the COOL FAN #1 fuse. The powertrain control module (PCM) controls the cooling fan 1 relay by grounding the low speed cooling fan relay control circuit via an internal solid state device called a driver.
Battery positive voltage is supplied to the cooling fan 2 relay and the cooling fan 3 relay from the COOL FAN #2 fuse. The PCM controls the relays by grounding the high speed cooling fan relay control circuit.
When the PCM is commanding a relay on, the voltage potential of the control circuit should be low, near 0 volts. When the PCM is commanding the control circuit to a relay, the voltage potential of the circuit should be high, near battery voltage. If the fault detection circuit senses a voltage other than what is expected, the DTC will set.
The PCM will monitor the control circuit for the following conditions:
• A short to ground
• A short to voltage
• An open circuit
• An open relay coil
• An internally shorted or excessively low resistance relay coil
When the PCM detects any of the above conditions, the DTC will set and the affected driver will be disabled.
It sounds like you have a control problem , The ECM or PCM energize the relay by supplying a ground or power depending on the manufacturer ! What make , year model vehicle ! P0481 Cooling Fan 2 Control Circuit Malfunction
Both radiator fan relay's ????? There are three relay's !
DTC P0481Cooling Fan Relay 2 Control Circuit
Circuit Description
Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding on. DTC P0481set indicates an improper voltage level has been detected, which controls the Cool Fan 2 and Cool Fan 3 Relays.
Check cooling fan maxifuse 15 amp. This fuse supply's B+ voltage too cool fan relay's 2 & 3 control side . The PCM supply's a ground to energize these two relay's , the PCM is not seeing the correct voltage that it should be . The fuse could be the problem , an open circuit , the transistor or driver as GM calls it output driver module . The number 1 relay is working fine , with A/C on # 1 relay is turned on or energized by the PCM for low speed operation .
There is a good video on youtube on how this three relay cooling fan system works an how to trouble shoot . Relay Driven Dual Cooling Fan Diagnostics
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