HVAC System not discovered in Scan Tool Scan

[FarmMechanic]

Hello,

Today I used my scan tool on my 2007 Nissan Xterra and was a bit surprised when the scan did not seem to show / find / discover any HVAC related systems.
This is actually the first time this has happened with ANY vehicle I have scanned.

It's as if the vehicle has no AC system, but it most certainly does.
Although as of two days ago it stopped working all of a sudden.
Anyone know of a reason why nothing related to any HVAC or Air Control would be present in a scan tool?
It's an Xtool D8 if that matters and it's updated.

I'm at a loss. Bad computer somewhere in the vehicle?

Thanks

 

[RTM]

Maybe bad CPU on the HVAC system? no one home to answer?

 

[dogdog]

was your auto ac ever discovered by your scan tools since 2007?

Not all ac modules are "discoverable" dunno too much about nissans, the VW MKIV 1999 - 2005 cars with manual AC systems are NOT discoverable only their Climatetronics are discoverable as "AC"

sounds like a 2007 Nissan specific question.

 

[Wrench97]

I don't see any can bus wired into the hvac control head, it appears the cooling fans and A/C request are controlled through the IPDM and ECU through the BCM.
If the HVAC module was down and on the network there would be codes in several other modules telling you it's missing.
Look in the ECM for the A/C request pid and the A/C pressure sensor readings.

 

[toolenthusiast]

Anyone know of a reason why nothing related to any HVAC or Air Control would be present in a scan tool?

Having a decent scanner is a start, but you’re still flying blind if you don’t pull service information before attempting a diag. The workshop manual will have a page calling Theory of Operation, or something to that effect. You’ll also have wiring diagrams, TSBs that can be filtered by system, a diagnostic flowchart for inoperable HVAC, and possibly a database of the most common fixes for the concern.

And yes, it’s quite conceivable that there is not an HVAC module. Bear in mind that the vehicle is a 2007MY, but that generation started production in 2004; the AC system design is a full 20 years old at least. (Example: a 2015 Econoline scans just like a 1996 Econoline, with ~6-7 electronic systems. PCM, TCM, ABS, SRS, GEM, not much else.)

In terms of direct advice: check for “lost communication with HVAC” codes. Google “2007 frontier no hvac”. If you’re incredibly lucky you might find a video on this concern from Pine Hollow Auto Diagnostics or South Main Auto. Preferably just get Alldata.

 

[2ndGearRubber]

It's likely not a module.

I would assume it's an input to either another module, like the BCM, or it's simply a component which allows for direct control of things.

If other modules aren't fussing about it with Comm codes, it's not offline, it's simply never been online.

 

[PCustoms]

It's likely not a module.

I would assume it's an input to either another module, like the BCM, or it's simply a component which allows for direct control of things.

If other modules aren't fussing about it with Comm codes, it's not offline, it's simply never been online.

Xterra are pretty dumb, and relatively unchanged since the 2nd gen got released in 2005. I would not expect a module.

 

[FarmMechanic]

Found this in the FSM.....