'92 300SE - alarm DTC's show none stored. Alarm tests all are successful except for those that involve attempting to start the car. i.e. Open door with alarm set - alarm sounds, etc.

I can set the alarm with the remote, and I get about 10 seconds of flashing red lights on the door handle. According to the owner's manual, this means the alarm has failed to arm successfully. If I leave the driver's window down, I can reach in, stick the key in the ignition and when I turn it to position 1, the alarm begins to sound. I can continue from there and start the car without difficulty.

P.O. had installed a remote starter aftermarket alarm on the car. I've removed same.

The factory radio is long gone, and I've identified the wire that used to hook to the factory radio as part of the alarm system. From what I can glean from the AllData circuit diagrams, this wire should be connected to ground when the radio is installed. Unfortunately, one place in AllData says 12v- should be present with the radio installed, the other place in AllData says 12v- should be present with the radio removed. I've tried grounding the wire at the connector to the alarm module in the trunk - still no change in the alarm's behavior. I don't think it would matter whether I ground the wire at its source or destination.

I suspect that the remote starter system involved branching around the K38 relay which is supposed to control the starter lockout part of the alarm system.

Looking in AllData, it would appear that the relay is either on the transmission hump up behind the radio, or up in the dash on the right-hand side behind all of the vacuum hoses for the A/C. I've checked the transmission hump location - nothing is there other than the brain box for the air bags. Pulling the glove box interior out shows most of the picture that AllData provides, but the relay is no where to be seen, either that or it's hidden behind the ducting - which I'm not eager to remove.

Any idea where I might find the K38 relay? Absent of this item, I'm afraid I'll have to resort to crafting my own starter interrupt which is something I'm not looking forward to.

The 1992 models do not have a K38 relay..that started on the 1993 Model year, except the W201 chassis(190's)

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OK - no K38 relay - where do I go next to isolate why I can start the car while the alarm is wailing away?