No Start Problem - Fuel Pump and Starter Relay not grounding

I have a no-start problem on my 1999 996 cabrio, and was hoping for some advice. The starter won't turn over and the fuel pump won't pump, and of course no-start. I have bypassed the clutch switch, and bench tested the relays for the fuel pump, starter and MFI, and all work fine. The fuses are all fine, and were tested with a VOM. I have a new starter switch, and all functions work fine except starting the car. The car locks with the key fob and the security LED flashes when locked. My fuel pump works when I use a jumper wire between point 30 and 87 in the fuel pump relay board, and the starter turns over when I use a jumper wire between points 30 and 87 in the starter relay board and turn the ignition to the start position. What isn't happening is for both the fuel pump and starter, point 86 is not grounding, nor is point 85 getting 12 volts when the ignition is on. For the MFI relay, I get 12 volts at points 30 and 86 with the ignition on, but point 85 is not grounding. I don't have a durametric scanner (I'm thinking it's time to get one). I did disconnect the battery and let it sit for a few hours. Is there any way to bench test the key chip reader, immobilizer or DME to see if one of them are not working? For additional background, the no-start situation occurred after I replaced the passenger door lock actuator, and I cleaned the ignition lock. I also did this without disconnecting the battery - which I know was violating the first rule of working on electrical components! Regarding cleaning the ignition lock, it had some red goo in it that I would see on the key, the black plastic cover in the lock opening was stuck open, and some of the tumblers would stick, especially when cold. My guess is a previous owner used a lubricant in the lock that hardened over time. I initially used WD40 to clean out the goo, using a bulb syringe to try to suck out the WD40. That did a decent job, but then I read to use CRC electronic cleaner, which did great job cleaning the lock. After waiting a couple hours, I used some graphite to lube the lock, and switched the key on and off several times to distribute the graphite. Then the car wouldn't start, so I checked the ignition switch, and found it had some of the red goo as well as WD40 residue, so I replaced it thinking the goo may have shorted something in the switch. Any advice or thoughts would be most welcome ( and please be kind about not disconnecting the battery - I am kicking myself pretty hard about that snafu)! Thanks much.

Take the bolts out of the drivers seat and lean it back to remove the alarm control unit/immobilizer. There is a 10 amp fuse in the end where the connector plugs in, see if it's blown.

Have you checked fuses C1 to C4 and E1? Sounds like your immobilizer is not enabling the starter circuit. My guess is you would need durametric to troubleshoot it further.

I checked the C1-C4 and E1 fuses, as well as immobilizer (although mine was a 15 amp), and all are fine.

You said you replaced the electrical part of the ignition switch. What part number did you use? I have heard of the exact same problem and it was the wrong switch.

are you sure you reconnected the airbag on the passenger side ?

I picked up the ignition switch from O'Reilly's. It has the 4AO.905.849B part number on the box along with Import Direct's part number 18-0550. It looks identical to the switch in the car. Regarding air bag, I never disconnected it. Thanks for sharing ideas though.

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Did you see/miss this post? ^^^ Have you checked this fuse?

I checked the immobilizer fuse as well as the C1-4 and E1 fuses. Did it with a VOM. All checked out fine.

this may help pinpoint issue - if the red alarm led is flashing twice every two seconds indicates a fault in the system .

It seems that you are getting +12V at all the right places, but you are not getting a ground. Have you checked the engine ground strap for corrosion or breakage? Also, although it is a PITA, maybe undo the engine bay wiring harnesses and clean up all the contacts with electrical cleaner. Check for the grounding point somewhere near the Relay Group 2...should be a brown wire to trace from the relay tray to a ground point somewhere nearby.

Thanks for the suggestions. Could you tell me where the engine ground strap is located? I am getting the two flashes every two seconds. Will a durametric scanner give me a closer diagnosis, such as defective key reader, immobilizer, DME, bad grounds? Thanks again.

I don't think the Durametric is going to help much in this situation. It really does not tell you much about the key reader, immobilizer, wiring, grounds and so on. It will tell you at least that the DME is alive. The engine ground strap is behind the passenger side rear wheel. Large wire that goes from the engine block to the frame.

This is a guess - supported by the alarm flashes - but I think the immobilizer/alarm is compromised -When you repaired the locking mechanism any chance you shorted a wire ?There are firms that can test /repair an immobilizer -ECU Doctors is one .Grounds is always a possibility but the car was working before the repair ( I assume ) .

Yes everything was working fine, except the passenger door lock and the ignition lock. I'll check the ground, but I'm thinking I damaged the key reader or immobilizer when switching the ignition on and off to distribute the graphite. I believe there is a coil in the key reader - maybe rapid heating and cooling when turning the key caused a problem, or something in the immobilizer. I see only two wires going to the key reader. Can it be bypassed?

Unfortunately the immobilizer cannot be bypassed -there is a handshake between the dme and immobilizer .ECU doctors and some other firms have developed alternative solutions -You might want to call them and discuss your situation -they might have some suggestions ..

Just to be 100% certain your fuses are simply good. Go back and test them with a common test light or anolog VOM. Very good Digital VOM's can read "ghost voltage" on complex electronics circuits. While most high qualilty DVOM's have a high impedance of 1Mohm, it's great for not affecting circuits by testing, but can lead to "ghost voltage" readings sending you off on a wild goose chase. "Ghost voltage" can be caused by a capacitor hooked in a complex circuit to an adjacent live curcuit. The low impedance of an anolog, or a simple test light, will not read "ghost voltage" and just simply tell you if the fuse is blown or not. Or pull the fuses out of the system and test for continuity..

I did test the fuses for continuity, and all tested good. I talked with ECU Doctors, and they suggested disconnecting the DME and Immobilizer, and I did the Key Reader too, which might re-set them. I gave it an hour in case there were some capacitors in them, and still no start after I reconnected everything. Does the immobilizer work on the fuel pump and starter circuits only? If so, would it be safe to try to start the car by jumping the fuel pump relay and starter relay? That might tell me if the DME, grounds and engine wiring harnesses are good, and isolate the problem to the immobilizer.

DME controls the grounds-Immobilizer passes a code to DME .

I would put a simple OBDII scanner/reader on the car and see if the DME can be read/is alive. If the OBDII reader returns anything that at least means the DME is alive. I can't believe all this transpired from replacing the passenger door lock actuator. I don't know how doing that would result in a problem with the DME/Immobilizer. I know you put in a new ignition switch as well. Do you have the old one around? Maybe swap it in just to test? The start up logic is this: 1) Locking and unlocking the car only means the security code for locking/unlocking is being transmitted by the key and the immobilizer recognizes it. 2) Insert key in the ignition switch. The key surround reads the passive RFID pill in the key and sends that to the immobilizer. If the key matches the immobilizer signals the DME and all is good to go. If it does not match, the immobilizer signals the DME no go, and the car will not start. Do you have one key or two? Have you tried both? Is the pill still in the key?

The immobilizer is telling via the led flashes there is a problem .I agree that the door lock probably didn't cause this .The ignition key issues are probably a root cause .Since there is software in there it probably got confused on the repeated on off cycles

I wonder if you knocked the wires loose from the key surround detector when replacing the ignition switch. I believe it is a small black box just above the ignition switch. Seems to me the car is not detecting the key.

I checked the wires on the pill reader box on the ignition, and all seemed fine. I checked the grounds, and they seemed fine. I can turn over the engine with the ignition switch if I jump the starter relay, and all other functions work, so I think the stater switch is okay. I ordered a Durametric scanner yesterday, and I'll check to see if the DME is working. It arrives next Thursday. Thanks for all the advice and I'll report back lare next week.

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The durametric won't arrive until Monday so thought I'd try a few things, but none worked. I unplugged the new door lock actuator and plugged in the original one, but car still wouldn't turn over. I cleaned the grounds by the DME and rear relays, although all were clean and the nuts tight, and wire crimps were tight. I jumped the fuel pump relay and the starter relay, and while the engine turned over and the fuel pump pumped, again no start. I double checked that the connections at the DME, immobilizer and key reader were tight, and tried wiggling the wires at the reader and on the ring around the key while turning the key, but no luck. I cleaned the ignition switch that was in the car with electrical contact cleaner and tried that switch, but no luck. It looks like it is either the DME, immobilizer or key reader. The durametric should tell me if the DME is working, and Specialized ECU Repair can test the Immobilizer, but is there any way that I can test the key reader?

Looks like I'll need either a key signal transducer or key lock cylinder. The durametric scanner couldn't read the DME, and I couldn't find any way to test if it was the key lock cylinder/transducer, or the demobilizer/DME. I sent the demobilizer/DME to ECU Specialized Repair and they both tested fine. Has anyone ever tested the key reader system? There are only two wires that go to the ring that surrounds the key opening so I would think there is a resistance value to test it. If it is the transducer, does that need to be programmed for my key by the dealer? Thanks for any advice.

The transducer, key surround detector, is only used for detection (reading) of the RFID pill in the key. What it detects is sent to the immobilizer. It is the immobilizer that is programmed to the key RFID pill. If the immobilizer does not detect the key, no go. If the immobilizer detects the key but it does not match, no go. Only when the immobilizer detects the correct key pill, then it makes a handshake with the DME telling it all is good to go. So in the end, it is the key pill and immobilizer that has to be programmed to match. Since it involves the security system of the car, I believe that only a dealer can access and program the keys and immobilizer. They have to request super secret information from Stuttgart.

The alarm system was flashing a fault -I think the durametric can pick up that code -if so what is it ?

He said the Durametric did not read the DME, so he sent it and the immobilizer to ECUDoctors. They said that they are both working okay. It is probably still in shipping back to him. If he can get the Durametric to read the DME, then maybe he can get the code(s). But I don't think that is going to happen...because...his problem is between the key pill and immobilizer. The immobilizer is not reading the key pill, so no power is going to the DME, therefore Durametric will not work.

If ecu doctors can test immobilizer you would hope they could also test the key and pill .Not sure but I think the alarm codes be accessed without the dme

Thanks DBJoe996 for the info on how the lock cylinder and transducer work - that certainly answers a couple other questions! It explains why ECU Doctors didn't ask for my lock cylinder and transducer, but did ask for one of my keys - they can use their own lock cylinder and transducer when testing the immobilizer/DME. That might also explain why used transducers are so inexpensive - they don't need to be coded to the car. Looks like it's narrowed down to the lock cylinder or transducer. Since I haven't heard of a way to test the lock cylinder myself (although you would think there is a resistance value to test it), the least expensive route is to buy a used transducer and see if that solves the problem. Thanks again and I'll keep you posted.

DBF- Glad you clarified that ECU doctors also checks the pill .Bet your car is running by next weekend

Thanks, and that's the goal!

DBF, I am curious to find out what the resolution to the no start condition was found?

hi, news?

Beating a dead horse here, but one thing jumped to me right away: the grease used was graphite - I hope that was used just for the tumbler not for the electrical part.