CLK-430 - No Crank, No Start
1) Insert key and the EIS makes it's usual Kla-click sound
2) Turn key to position #1 - Stereo Operates, Clock & Interface Illuminate, per normal
3) Turn key to position #2 (Run) - All dash warning lights illuminate and chimes normally
4) Turn key to spring loaded position #3 (Start) - Nothing happens. No additional sounds of any type.
Sub symptoms:
a) The shifter can be moved freely to any gear with or without key
b) When the key is in the ignition in the #2 (Run) position, the Gear Indicator on the dash correctly registers the proper gear as it's selected (P,R,N,D)
c) When the key is in the ignition in the #2 (Run) position, when shifting to R or D, the exterior parking lights and dash backlighting illuminate.
Battery is 6 months old, but I removed and tested it anyway. Confirmed good and fully charged.
No stored codes present.
Prior to this No start issue, occasionally the vehicle would not shift from neutral back into either Reverse or Park, but if you let the vehicle sit off for about 30 minutes, it would then finally let you shift it back into Reverse or Park. The key could be removed while the car was in neutral.
Secondly, the power windows and rear view mirrors ceased operating, but every time I disconnected and reconnected the battery, both the windows and rear view mirror would both function correctly again, but only for about a day - then back to their non responsive state. For the past 8 months, I've only been driving this vehicle once a week for 30 minutes for battery maintenance, and to let it stretch it legs. I took it on a 1800 mile roadtrip to pick up a new rear bumper cover last September, and she operated flawlessly. The issue with the "No Reverse/Park access, & windows and mirrors, started the week after that roadtrip.
Last edited by Aussiesuede; Jan 16, 2018 at 04:36 PM.




1) Insert key and the EIS makes it's usual Kla-click sound
2) Turn key to position #1 - Stereo Operates, Clock & Interface Illuminate, per normal
3) Turn key to position #2 (Run) - All dash warning lights illuminate and chimes normally
4) Turn key to spring loaded position #3 (Start) - Nothing happens. No additional sounds of any type.
Sub symptoms:
a) The shifter can be moved freely to any gear with or without key
b) When the key is in the ignition in the #2 (Run) position, the Gear Indicator on the dash correctly registers the proper gear as it's selected (P,R,N,D)
c) When the key is in the ignition in the #2 (Run) position, when shifting to R or D, the exterior parking lights and dash backlighting illuminate.
Battery is 6 months old, but I removed and tested it anyway. Confirmed good and fully charged.
No stored codes present.
Prior to this No start issue, occasionally the vehicle would not shift from neutral back into either Reverse or Park, but if you let the vehicle sit off for about 30 minutes, it would then finally let you shift it back into Reverse or Park. The key could be removed while the car was in neutral.
Secondly, the power windows and rear view mirrors ceased operating, but every time I disconnected and reconnected the battery, both the windows and rear view mirror would both function correctly again, but only for about a day - then back to their non responsive state. For the past 8 months, I've only been driving this vehicle once a week for 30 minutes for battery maintenance, and to let it stretch it legs. I took it on a 1800 mile roadtrip to pick up a new rear bumper cover last September, and she operated flawlessly. The issue with the "No Reverse/Park access, & windows and mirrors, started the week after that roadtrip.
1) Since the EIS would not let the key turn if a successful mating wasn't made, I've eliminated the Key/EIS as the culprit.
2) Since the Dash correctly identifies the correct gear, I don't thinks it's a TCU issue.
3) I replaced the brake light switch about a year ago, but if #4 doesn't solve the issue, I'll install another one just to eliminate it as a possibility since it's such a cheap potential solution.
4) This led me to the K40 Module in the right hand side fuse panel in the engine bay. I removed and inspected the relay and then jumpered circuit 87 & the car will start and drive.
So I'll first pick up a new starter relay on monday, and if that doesn't solve the issue, I'll remove the K40 Module for furthur inspection and potential replacement. I'll post the results to assist future searchers...




Fortunately, the solution was 'old school', involving only the power supply to the solenoid / starting motor.
The subject relay is the same multi-purpose relay, as used for the W208 fuel pump, the cabriolet hydraulic pump etc.and only a $6 part.
When switching high currents, the relay's 'make, break' contacts produce a spark, that in time, results in contact pitting, which then becomes a resistance to providing the required current to operate the motor.
Note: The engine immobilizer, shift control module and brake light switch, could have been checked as OK, by just measuring the ECU signal voltage at the relay's actuating coil terminals.
Last edited by Serndipity; Jan 26, 2018 at 11:16 PM.


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1) Insert key and the EIS makes it's usual Kla-click sound
2) Turn key to position #1 - Stereo Operates, Clock & Interface Illuminate, per normal
3) Turn key to position #2 (Run) - All dash warning lights illuminate and chimes normally
4) Turn key to spring loaded position #3 (Start) - Nothing happens. No additional sounds of any type.
Sub symptoms:
a) The shifter can be moved freely to any gear with or without key
b) When the key is in the ignition in the #2 (Run) position, the Gear Indicator on the dash correctly registers the proper gear as it's selected (P,R,N,D)
c) When the key is in the ignition in the #2 (Run) position, when shifting to R or D, the exterior parking lights and dash backlighting illuminate.
Battery is 6 months old, but I removed and tested it anyway. Confirmed good and fully charged.
No stored codes present.
Prior to this No start issue, occasionally the vehicle would not shift from neutral back into either Reverse or Park, but if you let the vehicle sit off for about 30 minutes, it would then finally let you shift it back into Reverse or Park. The key could be removed while the car was in neutral.
Secondly, the power windows and rear view mirrors ceased operating, but every time I disconnected and reconnected the battery, both the windows and rear view mirror would both function correctly again, but only for about a day - then back to their non responsive state. For the past 8 months, I've only been driving this vehicle once a week for 30 minutes for battery maintenance, and to let it stretch it legs. I took it on a 1800 mile roadtrip to pick up a new rear bumper cover last September, and she operated flawlessly. The issue with the "No Reverse/Park access, & windows and mirrors, started the week after that roadtrip.



