'99 S70 Base, N/A, Auto -- Cruise control INOP troubleshooting

[precopster]

Engage?? , energise?? Steve I think you may have watched afew episodes of Star Trek this week

[abscate]

"Make it so..." JLP



Evan - I don't think stalk swap is too nasty a job, but maybe its worth getting a PnP stalk to try it rather than double the labor. If it doesn't fix it, Ill buy it from you to replace my lack of "-" function.

Actually, thats 2.5x the labor, isn't it?

[E Showell]

Steve-- If a stalk swap does not work, I don't know what else I would try to remedy the lack of cruise control .

[precopster]

I have an idea !! Try the minus function first. If this also doesn't "engage :ugeek: " cruise control then remove the steering cover and try to locate the pinouts for the ON/OFF function. You don't need to remove the switch. The pinouts are in a white connector which is separate from the main body of the switch.

Try to locate a short which then changes to an open circuit when switch is off. Less wasted time:D I have an 850 cruise switch here. I'll get some pinouts for you.

[E Showell]

Thanks, Mike, but you are assuming I have some baseline competence in automotive electronics. That would be a mistaken assumption. I have no idea how to distinguish between a completed circuit an open circuit or a short.

[precopster]

Ok I'll bteak it down for you.

1) Buy $5 digital meter from thrift shop
2) Insert leads into ground and ohms sockets
3) Set meter to 2000 ohm range
4) Touch test leads together; reading should be 0.00 or close enough THIS IS A SHORT
5) Find test points at top right and bottom right of this connector in picture on grey and green leads.
6) When switch is off meter says "1" When switch is on meter says 001 ranging to 003 no higher if contacts are OK

[E Showell]

Thanks Mike. I'll try it and report back. (Already have the multimeter).

[abscate]

Here are your pin outs on the switch...it's component 3/4 on the diagram. Don't freak, electrical diagrams are a lot simpler than client discovery, it's just a new language...


When you move the engage switch, you should see both

Term 1 to term 2
Term 1 to term 3

Both go from open ( high resistance) to 0 ohm resistance as the switch is moved for OFF to CRuise. My guess is one of them, probably term1- term 2, will stay open or high resistance. Replace switch in this case.

Sidebar...the B47 input yo the switch is not a 12 VDC supply but a complex signal from the ECU. Don't put any voltage (including voltmeter on resistance scale ) on the ECU side of the connector. Testing in the switch side is Fine after you disconnect ( which you have to to access the terminals)

[abscate]

It's a pretty cool production feat to consider in the fly by wire cars..for the same cost as the earlier cars, all of the vacuum controlled cruise components are removed except the switch. It almost dulls the pain of the ETB assemblies on 99-2002 models...

[precopster]

Downside of the software cruise is if you don't have cruise on a 1999 base model (just like my deceased one that was written off) you are pretty much screwed except for a $500 visit to the dealer.