Trying to get the truck ready to pass inspection and I have the CEL with a code of P0413 and could use some help narrowing down the culprit.

Looking up the code I see its description is "P0413 Secondary Air Injection System Switching Valve A Circuit Open "
Does anyone know with a reasonable amount of certainty if this means that the SAI solenoid is to blame?

Troubleshooting steps I have done thus far.

I can confirm that the SAI pump is not running as it should on initial cold start.
The relay to the air pump checks out and I can run the pump powering it from the fuse box with the relay out of the circuit.
Looking at the SAI solenoid I can confirm that connecting both vacuum lines together that valves to the exhaust are opening.
The blowing through the vacuum fitting on the solenoid without power there is no resistance(its wide open Can anyone confirm if this is good or bad). I would think it should be closed until power is supplied.
Supplying power to the solenoid with it out of the truck does not seem to engage the solenoid.
Testing for power at the solenoid I get about 6 volts seems to be constant with the truck running

Looking at this diagram https://landroverforums.com/forum/di...ary-air-11849/
I feel as if the ECU is not sending the signal to power the air pump or solenoid perhaps that's because the solenoid is bad and the ECU can scenes that?

Any ideas or additional testing thoughts greatly appreciated.

 

Found this old thread, I am having a similar non-running SAI, now throwing a P0143 code.

Did you ever solve it? was it a problem with the solenoid? or was it the valves?

 

ALRB, how much have you troubleshot the SAI system?

 

Sorry for delay, my email notification on this thread went to spam.

I have done the following:

Tested the SAI pump by jumpering it at the relay socket -- it runs as loud as ever

Tested the SAI vacuum solenoid using 12v power source -- it opens when power is applied

Tested the SAI valves for tight closure by disconnecting the vacuum lines to them opening the pipes to the pump and then running the engine -- no exhaust leakage

Smoke tested the vacuum harness, discovered a leak -- broken plastic line -- and repaired it

I picked up spares of everything in the SAI system except the pump from a '03 with 100K miles on it in a junkyard. Haven't done anything with it yet.

 

Just dealt with this myself - one of the two wires on the back of the vacuum solenoid connector finally broke off. Spliced in a new connector - problem solved. Check all the old, brittle connector wires.

 

That code showing an open circuit means an open in the solenoid coil or open in the wires to the solenoid as Tony states

 

I have no codes on the D2 at the moment -- that's what is most frustrating.

But as a test, I did disconnect the SAI solenoid multiplug and then started the vehicle, and it threw the P0413.

Cleared code, plugged it back in and started again: no code.

So assuming wiring is OK as it's sensing the open properly with the connector unplugged.

 

Yes, sounds like it is working correctly, however your previous symptoms suggest you have an open in the circuit, Disco wires are know to break internally and give intermittent failures.

 

So far I haven't had to fix anything on the wiring harness other than eliminating those flaky the ABS/speed sensor connectors by hard-wiring new ones directly into the ECU multiplug -- and that was 6 years ago. Maybe it's about time I had a new harness issue