The code definitions are:
P1401 DPFE circuit voltage high
P1409 EGR Vacuum Regulator Circuit Malfunction
P1413 Secondary Air Monitor Low (The computer has commanded the air pump on during a self test and it did not respond)
these codes may have different cuuses; you may ahve more than one fault. for teh P1413, air pump failure is the most common cause, although there is a relay near the front of the FR fender that supplies power to teh air pump; I would check this before condemning an air pump assembly.
the 2 EGR codes may indicate a shorted DPFE sensor, a short to power in the DPFE circuit, or an open in the signal return (ground) side of teh DPFE circuit.
The EGR vacuum regulator solenoid is an electromagnetic device which is used to regulate the vacuum supply to the EGR valve. The solenoid contains a coil which magnetically controls the position of a disc to regulate the vacuum. As the duty cycle to the coil increases, the vacuum signal passed through the solenoid to the EGR valve also increases. Vacuum not directed to the EGR valve is vented through the solenoid vent to atmosphere. Note that at 0% duty cycle (no electrical signal applied), the EGR vacuum regulator solenoid allows some vacuum to pass, but not enough to open the EGR valve.The differential pressure feedback EGR sensor is a ceramic, capacitive-type pressure transducer that monitors the differential pressure across a metering orifice located in the orifice tube assembly. The differential pressure feedback sensor receives this signal through two hoses referred to as the downstream pressure hose (REF SIGNAL) and upstream pressure hose (HI SIGNAL). The HI and REF hose connections are marked on the aluminum differential pressure feedback EGR sensor housing for identification (note that the HI signal uses a larger diameter hose). The differential pressure feedback EGR sensor outputs a voltage proportional to the pressure drop across the metering orifice and supplies it to the PCM as EGR flow rate feedbackThe Differential Pressure Feedback EGR system consists of a differential pressure feedback EGR sensor, EGR vacuum regulator solenoid, EGR valve, orifice tube assembly, Powertrain Control Module (PCM) and connecting wires and vacuum hoses Operation of the system is as follows: