2005 Vz crewman 6 in limp mode loss of Speedo

[Tommyvz]

Hi guys I’ve got a vz crewman s 6 cyl that I use as a work car most recently it’s gone into limp mode check power train is going nuts and service vehicle warning also beeping like crazy especially when the Speedo drops out the trans position will flash on the cluster also showing what gear I’m in it’s like something is loose but I’ve checked earths cluster etc

The speedo drops out as does the digital one it will take off in drive but extremely slow worse than limp mode from 3rd
but you can drive it manually from 1st etc still taking off slow but a lot better than drive and it’s not slipping just slow to get going it’s showing codes po700 and po604

I’ve got a feeling it’s something to do with either the pcm or maybe a trans soliniod but just wanted to know if anyone else has experienced these symptoms before I start spending money on it any help would be appreciated cheers guys

 

[lout]

one post per fault please

https://forums.justcommodores.com.au/threads/vz-trans-issues-check-powertrain.242293/#post-3389525

 

[Tommyvz]

one post per fault please

http://[URL][URL]https://forums.jus...-issues-check-powertrain.242293/#post-3389525

[/URL][/URL]

one post per fault please

http://[URL]https://forums.justcomm...-issues-check-powertrain.242293/#post-3389525

[/URL]

Hi pretty sure it’s all going to be tied to the same thing not sure what your mean one post per fault sorry ??

 

[Fu Manchu]

It might be those things or it might not be. Unfortunately testing them requires equipment that most will not have or be able to use.

Bi-directional scan tools and oscilloscopes are required.

You could well be loading the parts canon. Gets expensive and frustrating.

I’d go see these guys in Dandenong. They actually do diagnostics properly and will nail down the fault through proper process, not guess work as most shops and dealers do.
https://theautomotiveclinic.com.au/

 

[Tommyvz]

It might be those things or it might not be. Unfortunately testing them requires equipment that most will not have or be able to use.

Bi-directional scan tools and oscilloscopes are required.

You could well be loading the parts canon. Gets expensive and frustrating.

I’d go see these guys in Dandenong. They actually do diagnostics properly and will nail down the fault through proper process, not guess work as most shops and dealers do.
https://theautomotiveclinic.com.au/

Thanks mate looks like ill definitely be loading the parts canon unfortunately thanks for the advice I might look at getting the car into those guys in Dandenong

 

[07GTS]

looks like those have a speed sensor on the gearbox, if that stops so does the speedo and gearbox dosnt know when to change gear, id test that first or even a scan tool that shows speed then if that drops out with the speedo prob issue, if speedo drops out but still shows speed on the data then u have other issues to find

 

[Tommyvz]

looks like those have a speed sensor on the gearbox, if that stops so does the speedo and gearbox dosnt know when to change gear, id test that first or even a scan tool that shows speed then if that drops out with the speedo prob issue, if speedo drops out but still shows speed on the data then u have other issues to find

Hey guys just incase anyone else has this issue turns out it was the pcm so replaced it with a second hand unit with the same numbers had a mate with a tech 2 clear the codes and presto no problems at all thanks for all the advice guys really appreciate it it’s a great forum