What Does P1435 Mean?
The PCM has detected that the secondary air injection pump relay control circuit is shorted to ground. This prevents the PCM from properly energizing the relay, keeping the secondary air pump from operating during cold start.
Common Causes
45%
Wiring harness damaged or pinched causing ground short
25%
Corroded connector with internal short to ground
15%
Failed relay with internal short to case ground
10%
Mounting bracket or metal component rubbing through wire insulation
5%
PCM internal relay driver failed shorted to ground
Diagnostic Steps
1
Step 1: Disconnect secondary air pump relay from socket
2
Step 2: Measure resistance between relay control circuit wire and ground - should read infinite resistance (open circuit)
3
Step 3: Wiggle and flex wiring harness while monitoring resistance to locate intermittent short
4
Step 4: Inspect harness routing for contact with ground points, especially at frame rails and engine mounts
5
Step 5: If wiring tests good, check PCM connector pins for corrosion or bent pins causing internal short
Estimated Repair Cost
$100 - $400
Parts + labor, varies by vehicle and location
The PCM has detected that the secondary air injection pump relay control circuit is shorted to ground. This prevents the PCM from properly energizing the relay, keeping the secondary air pump from operating during cold start.
The most common cause of P1435 (Secondary Air Injection Pump Relay Circuit Short To Ground) is: Wiring harness damaged or pinched causing ground short
Typical repair costs for P1435 range from $100 to $400, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to drive. Emissions may be elevated during cold starts and MIL will remain illuminated.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1435 to identify the root cause.
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Quick Info
Category
Powertrain
System
Emissions Control System
Difficulty
Type
Manufacturer
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