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1997 120k miles, hit the key, starts fine, turn off, hit key all lights come on but engine does not turn over, turn key off, turn on and it fires up, been going on for a year, any ideas? so far have changed theft deterrent relay and ignition switch, no change. Starter? , anything else to check?
What is the battery voltage across the battery terminals? --not the DIC reading. Battery voltage on a good battery fully charged should be 12.6 volts or slightly higher.
Check battery terminals are tight and clean. FSM says 11 foot pounds. You should not be able to move a cable connection at the battery by hand if it is tight.
The only way to determine what is causing your intermittent problem is to verify that the TDR is being energized each and everytime the key is turned to start the car. I would also check the cables at the starter solenoid, making sure they are clean and tight.
Measure the voltage between a groundpoint and all terminations on the TDR relay in the passenger footwell before and when you start the car and report back
Below is the location of the TDR relay shown in the passenger footwell above the body control module
Is the relay energizing ? ( Does the body control moule ground the A1 side of the relay)?
Does the TDR relay close contact between C1 and A2 when energized and put 12v volt from MaxiFuse 50 on to the purple wire ?
The TDR is the heart of the starting circuit, it is imperative that you verify its operation every single time the key is turned to the start position. You can insert a meter lead into the purple wire socket of the TDR and clip on the other lead to a ground to verify 12v is present and being sent to the starter solenoid. You might still have a problem with the Ignition switch module, some have been known to be bad straight out of the box, most of them are Made In China.
Most likely the Ignition switch start contacts are not making sometimes, the 12v power leaves the Ignition switch and then goes to the Park/Neutral switch or clutch safety switch if it's a M6 car and then to the TDR as a solid yellow wire. One final test will determine if it's the Ignition switch contacts, and that is to probe that yellow wire at the TDR and connect to ground the other lead and verify 12v is present evertime you crank the key to start the car.
okay, will try next, the ignition switch is brand new, could this be a key chip problem? going to try my spare key and see what happens, also have not pulled codes for awhile, will check it out tonight, thanks
I know you stated that the Ignition switch is new but some members of this forum have encountered problems with brand new switches. Try your second key and try spraying electronic contact cleaner on the very front part of the Ignition switch and on the key pellet. There is another measurement that you can try and that is probing the yellow black stripped wire at the TDR and the other lead to the supply side of a fuse you should show 12v.
I know you stated that the Ignition switch is new but some members of this forum have encountered problems with brand new switches. Try your second key and try spraying electronic contact cleaner on the very front part of the Ignition switch and on the key pellet. There is another measurement that you can try and that is probing the yellow black stripped wire at the TDR and the other lead to the supply side of a fuse you should show 12v.
knock on wood, tried spare key, so far has started every time. If so I can see my self dropping my keys and damaging the chip, because it started all at once.
Maybe, the chip in the key is really just a resistor that contacts in the very front part of the Ignition switch press against and are wired out to the BCM which recognizes that key as the correct one.
okay, put meter between purple and ground, when it starts, it goes up to 9v, then down to zero, when it does not start, no voltage
This indicate that the TDR relay is not energizing problably because the resitor in the key is not detected by the bodycontrolmodule
Maybe the slipring in the ignition key sensor need som more tention.
If you disconnect these two wires (black plug) and measure the resistance of the key through the wires the resistance value shall be 100% stable when the key is in the initionswitch
starting problems intermitent
