What does it mean?
P1434 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Secondary Air Injection System Pump Relay Circuit Short to B+ .
Symptoms
- MIL on with an incomplete secondary air monitor
- Air pump stays silent on cold start, because the coil sees battery voltage on both sides and cannot energise
- Elevated hydrocarbon emissions and a raw exhaust smell in the first minute after a cold start
- Blown fuse or an overheated PCM driver if the output is commanded on into the short
- Slightly rough cold idle and no pump response to a commanded relay test
Likely causes
- Control wire chafed against a live feed inside the harness
- Corrosion or moisture bridging the control and supply pins inside the relay socket
- Relay internally shorted between its coil and contact side
- Incorrect relay fitted, with a different pin layout than the socket expects
- Damaged wiring pinched between the fuse box and body, contacting a power circuit
- Faulty repair that connected the control line to a permanent live source
- PCM driver failed high, considered only after the harness checks are clean
How to fix it
- Remove the relay and inspect the socket for water, corrosion and melted terminals
- With the relay out and the PCM connector disconnected, check the control wire for battery voltage; voltage present proves a short to power
- Verify the correct relay part is fitted and the pin layout matches the socket
- Measure continuity between the relay coil terminals and the contact terminals to detect an internal short
- Inspect harness sections that run alongside power feeds for pinching and melted insulation
- Repair the shorted wire and reroute it away from live circuits and hot components
- Replace the relay if it is internally shorted, then confirm the pump runs for its normal cold start period and stops afterwards