What is it With The Darn Alarm/Antitheft Unit?

1615 Views 10 Replies 4 Participants Last post by Alfisto Steve, Jan 14, 2008

RexCars

Discussion Starter · Jan 10, 2008

Has anyone else had this problem: you put the key in the car and turn it, and you hear a little relay in the dash click and nothing more? No solenoid click from under the hood, no starter movement, no dimming of lights?

I have had this now in both my red 95 and my white 91. In the red 95, I found the relay under the dash that controls the starter and replaced it with a switch until my mechanic could bypass the anti-theft system and restore the car to key-start.

Last night the white 91 did the same thing in my garage at work. After I called AAA (and my buddy Jeff Greenfield), it occurred to me to try to start the car with the alarm armed rather than disarmed. That made the car go crazy, but when I finally got it switched off and killed the alarm, the car started right up. Clearly something in the alarm/antitheft unit had cut power to the starter solenoid.

Is this a common failure mode, or is this just my luck?

Rex in Albany

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Lazz

· #2 · Jan 10, 2008

argh!

on monday i drove home my 91 164s, and as i walked to the house i noticed the interior lights stayed on far longer than normal. just typical alfa electrical i thought, as the lights eventually went out. so wed i go to start her and same thing as you i get a relay click normal interior lighting and the led for the anti theft unit is blinking. however the alarm is in the off position at the siren. ive tried everything and my next step is a tow. if annyone has any info on this or an accurate description in bypassing the f'in thing for temp im all ears. thanks

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Del

· #3 · Jan 10, 2008

It does this (cut the ignition switch). I've had it happen when I've hit the lock fob at the wrong time, such as getting into the car, or with door open, I guess. You have to lock and unlock the car again with the fob to get the ignition switched back on. No big deal if you don't accidentally turn the alarm on at the wrong time.

Then again, maybe there IS something wrong with yours. Try to deliberately lock the car at the wrong time to see if it happens the way it should.

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Alfisto Steve

· #4 · Jan 10, 2008

Bypassing anti theft unit on 91-93 164 to enable starter

See my post about bypassing starter disable feature: http://www.alfabb.com/bb/forums/164...modify-enable-starter-wiring-91-93-164-a.html

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RexCars

Discussion Starter · #5 · Jan 11, 2008

Thanks Steve

That is exactly what I was looking for.

Rex

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RexCars

Discussion Starter · #6 · Jan 12, 2008

OK, Now What Do I Do?

I jumped the purple and purple and back wires to/from the alarm, and I also verified that on "start" I have 12 volts to the purple wire.

I'm still not getting any action from the starter or the starter solenoid.

I think I need to find the I10 starter inhibit relay. I assume it is one of the relays shown above, but which one? I don't think its the long one on the bottom or the one on top, because the color of the wires is wrong. In my 95 LS the relays were all sort of loose and I found the I10 based on the fact that it was the only one with purple and red wires. But I can's see the back of any of the relays in this car (its a 91S).

Any help on droping the relays or simply identifying the I10 relay would be great. I don't know if you can tell from the picture, but there are four relays on top (from back to front: tan, silver, silver, and gray with 15 amp fuse), one (with 7.5 amp fuse) below the third relay (from the front) in the top row and then the long one below.

Thanks,
Rex in Albany

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Alfisto Steve

· #7 · Jan 13, 2008 (Edited)

Are one or both of those silver relays a Bosch unit with red stripe if so that is starter relay? The part number ends in 112 and relay has a diode in it when red striped and that is one you need. Think it is top front one on 94-95 and bottom one on 91-93.

Is car automatic if so be sure gear shift in P or N and that switch is working. Do you have back up lights with key on and in R? A/T shifter switch in P-N has to ground I10 relay or it won't work.

Can you feel relay click when moving key to start? If so next you need to check pin 1 (black wire) in big round connector (G151) behind false firewall under hood above blower motor for 12v with key in start. You can also apply 12v power to socket 1 (black wire) in connector to see if starter solenoid will come alive.

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RexCars

Discussion Starter · #8 · Jan 13, 2008

Red Stripe Time

Thanks, Steve, red stripe it is. And it is the top front relay (from my perspective looking under the dash), so it should be relatively easy to reach.

It seems to me that the I10 relay is really in charge of the starting process. The purple wire through the anti-theft system tells it to energize when the key turns to start and this energizes the starter solenoid which spins the starter (in the best of all worlds).

So I will check for 12 volts on pin 30 (big red wire) and then try my switched jumper to pin 87. On the 95LS, the switched jumper would control the starter just fine. We shall see whether this works or whether the starter is bad. I'm not sure this car will survive if it is.

Car is 5 speed, not auto (did they put the auto in the S, it seems to be a contradiction in terms to me). Is there a test I should be doing with the backup lights?

Thanks again,
Rex

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Alfisto Steve

· #9 · Jan 13, 2008 (Edited)

RexCars said:
Thanks, Steve, red stripe it is. And it is the top front relay (from my perspective looking under the dash), so it should be relatively easy to reach.

It seems to me that the I10 relay is really in charge of the starting process. The purple wire through the anti-theft system tells it to energize when the key turns to start and this energizes the starter solenoid which spins the starter (in the best of all worlds).

So I will check for 12 volts on pin 30 (big red wire) and then try my switched jumper to pin 87. On the 95LS, the switched jumper would control the starter just fine. We shall see whether this works or whether the starter is bad. I'm not sure this car will survive if it is.

Car is 5 speed, not auto (did they put the auto in the S, it seems to be a contradiction in terms to me). Is there a test I should be doing with the backup lights?

Thanks again,
Rex

Test pin 30 to 87 will only prove starter will work only if pin 1 wiring in G151 connector good. You still have to get pin 30 juice to starter through pin 1 in connector. Ask me how I know this after a starter pull/change later and still no joy.

No auto in a S, but you did not say models of 164 you had just the years no models or tranny set up. MIGHT I suggest you modify your signature profile and add car info so it shows up when you post. There is only one of me and many of you so I just can't keep everybody and what 164 they have straight when answering posts.

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RexCars

Discussion Starter · #10 · Jan 14, 2008

Thanks, Steve

The I10 relay seems fine. Just to be sure, I replaced it with one from my parts car, with the advantage that I could look at the wiring on the back to be sure it was I10. On both 91s (my S and the parts car B), the I10 relay has a fuse holder with a 15 amp fuse in the base.

Anyway, I can feel the click, so its either the connector you mention or the starter. Car has 144,000 miles, but the starter was changed for a new one about 30,000 miles ago. That's a nasty job and one that I'm not sure about doing for this car. Still I'd hate to drive anything else this winter.

Where precisely do I find G151? On the 164B, I seem to recall that it was behind the false firewall somewhere. Can you tell me which side it is on and what I have to pull to get to it?

Thanks,
Rex
too embaressing to list all my Alfas, the 164s are a 91S and a 95LS 5 speed.

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Alfisto Steve

· #11 · Jan 14, 2008 (Edited)

With hood open you have to remove plastic cover over a/c system behind false firewall and locate larger of two round connectors. It is/was snapped into a mount close to blower motor. Unscrew two halves from each other and locate pin 1 check for 12v with key in start if you have 12v it is best to use some silver laced electrical paste in pin 1 socket in other half and hook back together and see if starter will now work. You can also directly apply 12v power test wire to socket 1 and see if starter will work. If still no joy get under car and verify small black wire from socket 1 is in fact hooked to starter solenoid behind heat shield. Check for 12v at wires end at starter with connecter connected and key in start before you call in the tools to remove starter.

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What is it With The Darn Alarm/Antitheft Unit?

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