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Cruise Control not working: any ideas ? (read below)

PostPosted: Tue Feb 23, 2021 7:06 pm
by klam
Hi,

so my subaru is still going relatively well, just had another major service done at 210K and it was not cheap as I had to get the power steering pump reconditioned and all the timing belt, spark plugs, water pump and plus some bushing like the ones that hold the AWD rear diff (front and back), cracked CV boot and list goes on...

During the above service, I've provided a new neutral possition switch sensor as I had an engine light come up before (occasionally) with the error indicating a fault on that one.. so it appeared all good however, I was still unable to engage the cruise control.
Then at the service they found some blown fuses (2) and that my rear right light is not working even after a replacement and that I need an auto electrician to look at it, and in addition to that the break light switch wasn't responding to OBD scanner with ON/OFF which indicated a fault in it.
So I got a mobile auto electrical expert to rock up and he managed to fix the break light switch, but unfortunately the cruise control is simply not not engaging. When I press it, the CRUISE lits up, but setting it up by pressing the other level down does absolutely nothing.
OBD scanners are reporting everything fine and no errors are logged:
- neutral position sensor (when in neutral = OFF, when in gear = ON)
- brake light switch (ON / OFF)
- clutch switch (ON / OFF)
- Cruise control switch (ON / OFF)
- Acceleration / Set switch (ON / OFF)

so it all appears to be in running order, but it's simply not setting the cruise control... Any ideas anyone ? Cheers ;)

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Tue Feb 23, 2021 8:54 pm
by bigBADbenny
this rings a bell but I'm needing time to think on it.

the ecu signal for NPS seems reversed?

I'd have to log mine to check vs yours.

Did you find the fault in your FSM?

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Wed Feb 24, 2021 8:06 am
by klam
thank you.

the same occured to me with the NPS switch ... but not sure how it really should be so thanks for checking ! I'm not sure if this can be reversed though as from what I remember the plug style end would be hard to put other way around.

Sorry, what's FSM ? There are no faults logged in the ECU at the moment. There was one ago indicating the faulty NPS switch

It was ages ago since I've logged into the ECU with one of my OBD cables, but since I've changed the computer seems like I have troubles with the drivers as the ECU explorer fails to connect.. any ideas where could I source them.. i know there were many different types from ebay seems like I will just keep trying installing different drivers each time.

[UPDATE]
Finally managed to log into my ecu via ecuexplorer. I can confirm that when in neutral NPS = 0, when in gear = 1. Can you please check yours and let me know. Much appreciated.

TA

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Sun Oct 10, 2021 9:37 am
by bigBADbenny
Did you resolve the issue?

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Sun Oct 10, 2021 3:47 pm
by subyroo
klam wrote:Sorry, what's FSM ?
TA


FSM = Factory Service Manual.
Factory Service Manuals are more specific and detailed, while Workshop Manuals are general.

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Sun May 29, 2022 7:48 am
by klam
Hi @BigBadbenny, no I haven't, I was hoping you could send me the correct/verified values for the sensor so I just gave up. Thanks

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Mon May 30, 2022 9:10 am
by bigBADbenny
I’d try the cruise control diagnostics in the FSM for your year model and transmission.
Link in my signature ;)

The system relies on many sensors & switches etc, so you’d be looking for an issue that might not throw a cel/DTC, but still disable setting cruise.

Re: Cruise Control not working: any ideas ? (read below)

PostPosted: Thu Sep 01, 2022 4:51 pm
by Ric
Have you changed your stop lights to use LEDs?
Reportedly this can stop cruise control working, as it needs to see the globe voltage fall below a set threshold.
(Otherwise it thinks you have your foot on the brake)
Often you need to wire a resistor in parallel with the LED globes to ensure this. Just popping some incandescent globes in as a test would quickly prove if this is the problem.