Recently poped a single check engine code: P1412. Diagnosed the problem with a fellow member over the phone and we concluded that the secondary air intake reservoir vacuum canister is bad. Part looks like this:

as a temporary measure I disconnected the thin tubing from both ends of the canister and connected them directly together thus bypassing the canister completely. I have every intention of replacing the canister - eventually. Used my "connections" at JiffyLube to clear the code. Now about a week later the service engine light popped on again, this time with 3 new codes: P1590, P1171 and P1174. Did a brief lookup in the Autozone computer and found several references to Oxygen Sensors (there is no Land Rover code thing in their system). With that in mind the previous owner told me that the truck needed O2 sensors.

While I was there I had them check my battery and the computer said the battery needs to be replaced but is charged at 80%. I figured the battery was bad becasue my AUX lights would turn off on their own after less than a minute of being turned on.

So afew questions I have here:
- Can a bad battery trigger any check engine codes or trigger any faults in the vehicle?
- Do these new codes correspond with bad O2 sensors? Or could it be something else?
- Do any of these codes correspond to my bad air intake vacuum canister and my tempo bypass setup?
- I'll be replacing the battery soon. Duralast Gold with a 8 year warranty or Optomia battery with 3 year warranty?
- I still have a extra Duralast Gold battery from my former 98 Disco 1. Apparently the battery is not very old, but ever since I parted out the truck the battery has been left outside under a tarp. Would a battery compatible with a Disco 1 also be compatible with my 2004 Disco 2? AZ said they would give it a super charge and test it to see if its still good and if so I could potentially save $119 if its compatible with my current truck.

Thanks much for your help here.

 

Certainly a bad battery could cause codes. A code is thrown when a sensor reads something out of range. It is just sensing an electrical signal/resistance/voltage. A bad system voltage means those readings could be off as a result.

As for your codes:

P1590 - ABS rough road signal circuit malfunction
P1171 - System too lean (bank 1)
P1174 - System too lean (bank 2)

Either BOTH of your O2 sensors went at the same time and your ABS sensors are working...but the computer doesn't know what it is.

 

I did read some place in the forum how the secondary air system does check the O2 sensors at startup, or something to that matter. I just went and found the thread that has a very detailed description (with diagrams) of the secondary air system. Here is the link. https://landroverforums.com/forum/di...ary-air-11849/

I would look at getting your secondary air issues resolved first since you don't have it in orginal working order at the moment.

Have you checked / changed the filter on the Secondary Pump itself? Have you ruled out the soleoid for the Seconday Air system?

I had secondary air codes be thrown and I replaced the solenoid, quick tied all of the hose connections for the secondary air sytem to their connections to insure they were tightly connected (no air leaking out at the connections) and then changed the filter on the pump itself and also sealed the two seams where the different sections of the pump connect, between the rivets on the pump. The code for the secondary air system has not tripped anymore codes.

How did you determine it was the vacuum canister on yours?

I did have an 02 sensor trip shortly after, replaced one front bank and now three weeks later the other front bank is giving me grief so I just ordered another 02 sensor to replace it.

 

There are 4 O2 sensors correct? 2 in the front and 2 in the rear?

I'm not very competent in diagnostics so threalassmikeg guided me through the process over the phone and he would be better suited to explain how we determined that the canister is bad. We checked various hoses, made sure their was suction, tried disconnecting and reconnecting connectors etc. So without more detailed info in the matter should I first purchase a replacement canister BEFORE going out and buying new O2 sensors? RoversNorth is the only place that sells them new but they have to special order them directly from Britain. Price is only $100 shipped so I can do that in afew weeks.

Should I invest in a new battery first or the canister?

 

Personally, I would put the cannister back on until you get a new one unless the vehicle runs really rough with it place. If you removed the cannister and the vehicle runs better then great but if not stick it back on.

If you can only afford one thing at a time, trust me I know what that's like as all my money has been going into my Disco over the last six months with the head gasket next, then replace the battery if its not holding a charge properly. Without a good battery you have a big paper weight!

Also, email the sales people @ britishparts.co.uk (sales@britishparts.co.uk) - I have ordered a couple of times from them for parts, prices are good even with the currency exchange in Canada and the US, and they ship DHL international express. Shipments to me in western Canada have arrived in 2 days. The shipment goes through the US first before coming here so you might get it in a day... seriously! Even when a part did not show on their website, they were able to get it for me. Most of their parts a very well priced and some others, no cheaper than buying them in the US.

Check it out.

Oh and if after charging your old battery and it checks out, there should be no reason why you can't use it in your newer Disco. If it wasn't undersized for the D1 and everything worked then there will be no difference unless you are constantly running a lot more accessories in the newer disco.

 

Agreed.
http://enginecodemaster.com

Engine Code: p1412

Land Rover Engine Code: P1412 = SAI system fault (LH side) ‐ air delivery not reaching catalysts

Click to Process more Land Rover Engine Codes here

 

You might be able to get a canister from a salvage yard or a dismantler like Paul Grant. If yours has a crack perhaps some JB Weld would help you out.

From the RAVE a slightly different code explanation:

during passive test)

The system does indeed do a functonal test of components.

 

P1412 has not returned since I bypassed the canister and reset the codes. I have not noticed any difference in driving from before I bypassed it either. Currently I have 3 codes: P1590, P1171 and P1174 and according to enginecode.com

P1174: "System too rich (bank 2) Additive injector adaptive fuelling - rich limit exceeded RH bank" - Not sure what that means... But I always use Gulf brand premium fuel and every once in awhile I use fuel injector cleaners.

P1171: "Lean Fueling Fault" - again not sure what this means

P1590: ABS rough road signal circuit malfunction: the lengthy description says the hardware is okay but SLABS ECU is sending an error signal.

I assume that the P1590 is related to my recent brake job and improper bleeding precedur. Spike said I need to rebleed the system and start with the SLABS using a special computer, then bleed to brake master cylinder and finally the wheels/calipers.

 

The vac reserve container is there so that when the system calls for it by computer, vac is available even if you have it floored going up hill and have low vacuum. There is most likely a check valve associated with the canister so that the vac reserve is not drawn off by other vacuum users upstream.

 

Well if I can avoid having to purchase another battery then I will buy a brand new canister from RoversNorth next week and see what happens. Maybe my canister is clogged or something. If this part is as important as implied here then Id rather just spend $100 and buy it new.