Car won't start!...and it's not the Steering Lock...

wheee!

First of all, the clutch switch may look identical to the ASCD switch.

Internally, the clutch switch is two sets of 'points' that do not make contact in the resting position. When you depress the clutch, the plunger goes into the switch and allows the two sets of 'points' to contact and create the closed loop required for ignition. Basically telling the car that the clutch is fully depressed.

The ASCD switch can be configured in exactly the opposite condition. Closed when at rest and open when pressed.

THEREFORE: Tracie's issue may indeed be the switch you are looking at . The one that determines that the brake pedal is fully depressed before allowing the car to start. At rest or pedal not pressed, the switch is resting open at the top of it's travel. When she steps on the brake to start the car, it closes the switch and changes state. Sometimes the contacts are fully touching with the pedal pressed and the car starts. At other times, like my clutch issue, the contacts or points have become oxidized and are not making full contact. I would pull the switch, open it, and sand the points lightly. That's all I did to fix mine!

Again, this is me hypothezising as I have not seen Tracie's issue before either. That and no one in Canada owns an auto....

__________________

JARblue

Can be configured that way or is configured that way? If the ASCD brake switch is closed at rest, then your cruise control scenario makes perfect sense.

Since the clutch switch interlock switch that enables the car to turn on is open at rest, it would make sense to me that the 7AT brake switch operates similarly. With the clutch pedal, I can push it 95% to the floor and the car still won't turn on. If the AT version requires that you push the brake far enough to enable the brake lights, then it follows that the stop lamp switch is the likely culprit. Someone with a functioning switch in their AT could check this by pushing the brake pedal but not far enough to trigger the brake lights and see if the car turns on.

If the ASCD switches are indeed closed circuit at rest and are responsible for permitting the car to turn on, you should be able to turn your car on as soon as the pedal (clutch for 6MT, brake for 7AT) travels far enough to open the switch circuit, which would be barely any travel at all.

Of course, your scenario where the ECU reads the position of both switches makes sense as well. The pedal barely has to be pushed to open the circuit of the ASCD switch, but the pedal also has to be pushed far enough to close the circuit of the second switch.

__________________

wheee!

I agree. However the starting issue would most likely be the one that releases the switch pressure when pushing the pedal. This should also be the one that controls the brake lights. Pedal pushed = okay to start and brake lights on.
The other switch would be for cruise control I would think. Letting the system know if the pedal was pushed to deactivate the cruise.... no?

__________________

ChrisSlicks

It's all up to the ECU programming. Normally open vs normally closed doesn't a lot of difference in the world of electronics. In fact the switches may work together in such that they must be in agreement (opposite states for verification).

__________________
Hotchkis ARB | Stillen CAI | Art Pipes | Berk CBE | Stillen AP Racing Brakes | AE Performance Oil Cooler | BC Racing ER Coilovers | Doran Control Arms

JARblue

I guess we'll start with the stop lamp switch and just take it out to see if there's anything malfunctioning.

__________________

wheee!

Good point Chris. It's best to open the switches and clean the contacts properly anyways. That might solve her issue completely...

__________________

JARblue

Sounds like we may just want to go ahead and pull both switches and clean them out for maintenance. I think we'll start with the stop lamp switch just for troubleshooting purposes. But even if that solves the problem, it may be prudent to clean the other switch as well.

I would guess that the switches are ON or OFF with no in between (i.e. digital signal), but is there any chance the "start delay" could possibly be related to dirty contacts in one of these switches?

__________________

wheee!

I feel bad for not taking pictures when I had the switch apart. I was in a hurry to fix the problem!

The switch is uber simple. A straight pole pushed through the body of the switch to allow the contacts to close and create a 'short' condition. No electronics, no logic circuit, nothing more than a mechanical set of points making contact.....

__________________

JARblue

No worries There is a lot of good information in this thread As long as they're easy to remove, which they appear to be from the service manual, I'll be happy. The only thing I'm not looking forward to is working down in the foot well

__________________

wheee!

They are easy to remove. Unplug the harness (release tab is closest to the switch part itself). A 14mm wrench will undo the locking nut, then just unscrew the switch from the mount.

The switch is then enclosed by two tabs that can be gently pried open with a jewellers screwdriver and then the switch will come apart. Be careful you don't dump the contacts and spring all over the place! It is a simple switch and goes back together easily.

__________________

wheee!

Anyone solve their delay start with this method yet?

__________________

wheee!

Any updates on tracies car Jar?

__________________

Pintsize725

Nope, we've both been too busy to arrange anything.

__________________
Tracie

370z_2910

wheee!

do you still have issue starting your z?

how about the steering lock harness connector?

does it resolve the starting problem?

wheee!

My issue has been 100% resolved with this method. I have the new generation steering lock and the harness is intact. The fuse is still in but I will pull it again probably one day.

Let me repeat: THIS PROBLEM IS 100% RESOLVED WITH THE CLEANING OF THE CLUTCH SWITCH!

__________________