alarm diagnosis without 9288 / 9540
10-07-2012, 06:27 PM
#1
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Thread Starter
alarm diagnosis without 9288 / 9540
Ok - I'm finally going to wade into diagnosing my factory alarm on my '94 (US).
What is happening is that after I lock my car, the alarm will go off after, say, 10 minutes.
I'd like to restore it to working condition. I understand many just disable the thing, but I'd just like it to work.
I believe this didn't happen when I got the car. I did install a replacement Blaupunkt shortly after I got the car. I used a harness adapter plug it didn't include the alarm wire. I seem to recall that I tied it into a ground connection on the frame of the receiver. I can't say if that's when my problem started, but it just may be, huh?
I have the WSM pdfs, but the alarm content in the PDF ends after page 90-17. It looks like life would be much easier with the 9288 and 9540 special tools. I doubt there's any chance in the world I'd be able to get those? So, this limited info from the WSM isn't very helpful. Therefore I'd like to get a few of the basics about the alarm so I can devise my troubleshooting strategy:
1. Where is the alarm control unit located? I understand it's under my passenger seat. I've never removed that, is it necessary? Is it easy? How should I go about that?
2. There are two main connectors on the alarm unit. Connector 1 seems to be the outputs with Connector 2 being the inputs (sensors). Is this right?
3. How does a sensor activate the alarm? Is is a source or sink of current? I believe it's a sink (ground) connection.
With these basics, I suspect a strategy for my problem is to find out which, if any, of the sensors is activating the alarm. So, I'd just disconnect the sensor connector, and, with all the doors closed, see which sensors are grounded. If one is grounded, that's where the fault is that's triggering the alarm.
Any pointers?
Thanks, Matt
What is happening is that after I lock my car, the alarm will go off after, say, 10 minutes.
I'd like to restore it to working condition. I understand many just disable the thing, but I'd just like it to work.
I believe this didn't happen when I got the car. I did install a replacement Blaupunkt shortly after I got the car. I used a harness adapter plug it didn't include the alarm wire. I seem to recall that I tied it into a ground connection on the frame of the receiver. I can't say if that's when my problem started, but it just may be, huh?
I have the WSM pdfs, but the alarm content in the PDF ends after page 90-17. It looks like life would be much easier with the 9288 and 9540 special tools. I doubt there's any chance in the world I'd be able to get those? So, this limited info from the WSM isn't very helpful. Therefore I'd like to get a few of the basics about the alarm so I can devise my troubleshooting strategy:
1. Where is the alarm control unit located? I understand it's under my passenger seat. I've never removed that, is it necessary? Is it easy? How should I go about that?
2. There are two main connectors on the alarm unit. Connector 1 seems to be the outputs with Connector 2 being the inputs (sensors). Is this right?
3. How does a sensor activate the alarm? Is is a source or sink of current? I believe it's a sink (ground) connection.
With these basics, I suspect a strategy for my problem is to find out which, if any, of the sensors is activating the alarm. So, I'd just disconnect the sensor connector, and, with all the doors closed, see which sensors are grounded. If one is grounded, that's where the fault is that's triggering the alarm.
Any pointers?
Thanks, Matt
10-07-2012, 07:25 PM
#2
Chronic Tool Dropper
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The factory radio bucket has a switched attachment for the alarm wire, and the radio bucket is grounded. If you just ground the alarm wire, you risk problems. I recommmend that you disconnect that sensor wire and isolate it, then see if the problem goes away. The radio bucket connection is shared with the hood switch too, electrically.
10-07-2012, 09:20 PM
#5
Chronic Tool Dropper
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The alarm system isn't really smart enough to communicate with the computer controller diagnostic tools.
10-14-2012, 01:07 PM
#7
Instructor
Thread Starter
Here's what I've learned:
I'm able to arm the alarm in the garage and the alarm doesn't go off unexpectedly. That is, after 15-30 seconds or so, the door LED posts blink. Then the alarm didn't go off by itself, which is good.
The behavior I had happen (maybe a year ago) was that I'd take a short trip, then lock the doors, then the alarm would go off after 10 minutes or so.
Now, last night when I was testing it in my garage, I noted that the LED posts gave a "double blink" which I believe means that one of the alarm circuits was tripped when arming it, and therefore that circuit was bypassed. Can someone confirm that?
I confirmed that the radio frame (a recent Blaupunkt) was grounded with a multimeter. The alarm wire from the harness just connects to the radio frame (there's a screw stud, so I have a short jumper to this stud from the alarm wire spade connector).
I did disconnect the wire attached to the radio frame, then locked the car. Double blink, just like last night. The alarm doesn't unexpectedly go off, but it still is a double blink.
I've confirmed that the hatch and doors activate the interior lights when opened, exactly as it should. I removed and inspected the hood pin switch and it looked okay. The switch also seemed to work when I had it removed and tested it with a multimeter.
So, now I've removed the passenger seat to access the alarm module and wiring. Is there a way I can identify which alarm circuits are tripped from the alarm wiring connectors?
Perhaps I need to study the wiring diagram some more, but I'm amazed a simple diagnostic procedure isn't outlined in the WSM. Geez, it's just an alarm!
I'm able to arm the alarm in the garage and the alarm doesn't go off unexpectedly. That is, after 15-30 seconds or so, the door LED posts blink. Then the alarm didn't go off by itself, which is good.
The behavior I had happen (maybe a year ago) was that I'd take a short trip, then lock the doors, then the alarm would go off after 10 minutes or so.
Now, last night when I was testing it in my garage, I noted that the LED posts gave a "double blink" which I believe means that one of the alarm circuits was tripped when arming it, and therefore that circuit was bypassed. Can someone confirm that?
The factory radio bucket has a switched attachment for the alarm wire, and the radio bucket is grounded. If you just ground the alarm wire, you risk problems. I recommmend that you disconnect that sensor wire and isolate it, then see if the problem goes away. The radio bucket connection is shared with the hood switch too, electrically.
I did disconnect the wire attached to the radio frame, then locked the car. Double blink, just like last night. The alarm doesn't unexpectedly go off, but it still is a double blink.
I've confirmed that the hatch and doors activate the interior lights when opened, exactly as it should. I removed and inspected the hood pin switch and it looked okay. The switch also seemed to work when I had it removed and tested it with a multimeter.
So, now I've removed the passenger seat to access the alarm module and wiring. Is there a way I can identify which alarm circuits are tripped from the alarm wiring connectors?
Perhaps I need to study the wiring diagram some more, but I'm amazed a simple diagnostic procedure isn't outlined in the WSM. Geez, it's just an alarm!
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10-14-2012, 02:29 PM
#8
Electron Wrangler
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Well - this is the later alarm unit that is actually diagnostically enabled. Need a Hammer or equiv.
There are 2 radio triggers so be carefull what you have - both are ground connection types - one triggers on OC to ground the other on SC to ground. The normal factory config was to connect the OC trigger to the isolated top radio cage - so the head unit's metal frame grounds it - so when removed from the console the alarm would trigger. The other is one left disconnected normally.
This is not shared with the hood switch on the later module.
The alarm unit is under the passenger seat under a metal cover - you must remove the passenger seat to access it. There is no other way. Warning the bolts may be loctite'd - heat if tough to remove...
The intended diagnostic method is to connect a Hammer and read out the recent alarm trigger events - its actually the best way to diagnose an alarm - but you need a hammer to do it.
Connector I is primarily higher powered connections (bigger connector)
Connector II is primarily sensors/triggers (smaller connector)
Double blink means one of two things:
1. Arming happened with one (or more) sensors tripped (idea is to see this when arming)
2. The alarm alerted since you armed it normally.
The most likely culprit after driving - is the hood switch (adjustment) have you moved the hood, changed gas struts etc?
I'd isolate the wire to the hood switch and see if that resolves your problem....
Alan
There are 2 radio triggers so be carefull what you have - both are ground connection types - one triggers on OC to ground the other on SC to ground. The normal factory config was to connect the OC trigger to the isolated top radio cage - so the head unit's metal frame grounds it - so when removed from the console the alarm would trigger. The other is one left disconnected normally.
This is not shared with the hood switch on the later module.
The alarm unit is under the passenger seat under a metal cover - you must remove the passenger seat to access it. There is no other way. Warning the bolts may be loctite'd - heat if tough to remove...
The intended diagnostic method is to connect a Hammer and read out the recent alarm trigger events - its actually the best way to diagnose an alarm - but you need a hammer to do it.
Connector I is primarily higher powered connections (bigger connector)
Connector II is primarily sensors/triggers (smaller connector)
Double blink means one of two things:
1. Arming happened with one (or more) sensors tripped (idea is to see this when arming)
2. The alarm alerted since you armed it normally.
The most likely culprit after driving - is the hood switch (adjustment) have you moved the hood, changed gas struts etc?
I'd isolate the wire to the hood switch and see if that resolves your problem....
Alan
Last edited by Alan; 10-14-2012 at 07:21 PM.
10-14-2012, 05:00 PM
#9
Instructor
Thread Starter
Thanks Alan.
The hood switch as a culprit makes sense. The switch mounting bracket was solid, the sensor itself doesn't snap tightly into the mount.
No recent changes have occurred with the hood. Same gas struts.
However, no matter if I remove the pin switch (leaving just the two pin connector base) or if I install a jumper on the two pin base, I go and lock the door and I still get the double blink.
So, it's either another circuit that is tripped, or I have multiple circuits tripped.
The radio security wire on my car is the brown/yellow. The radio was the Alpine unit with a single security wire out the back. The alarm wire from the harness just connected to this wire. I wouldn't have both radio alarm connections would I? I would expect just this one. If so, attaching it to the radio frame should be fine, as long as the frame is grounded (which it is).
It should be possible to check each of the alarm circuits individually?
From the wiring diagram, there appears to be just the following five sensor circuits:
Doors (Connector 2, pin 21) - tripped if grounded (pin switch is closed when door opens)
Hood (Connector 2, pin 5) - tripped if grounded (pin switch is closed when hood opens)
Hatch (Connector 2, pin 3) - tripped if grounded (pin switch is closed when hatch opens)
Glove box (Connector 2, pin 16) - tripped if grounded
Radio (Connector 2, pin 9) - tripped if ground DISconnected
I'm not sure what terminal 15, 30, and 61 are. I guess that terminal 30 is +12v and terminal 15 is accessory. Terminal 61 attaches to the ignition control (EZK?), which I would assume is an engine disable output.
My passenger seat is off and I've got complete access to the alarm module. I'm going to test my thinking with the sensor circuits.
The hood switch as a culprit makes sense. The switch mounting bracket was solid, the sensor itself doesn't snap tightly into the mount.
No recent changes have occurred with the hood. Same gas struts.
However, no matter if I remove the pin switch (leaving just the two pin connector base) or if I install a jumper on the two pin base, I go and lock the door and I still get the double blink.
So, it's either another circuit that is tripped, or I have multiple circuits tripped.
The radio security wire on my car is the brown/yellow. The radio was the Alpine unit with a single security wire out the back. The alarm wire from the harness just connected to this wire. I wouldn't have both radio alarm connections would I? I would expect just this one. If so, attaching it to the radio frame should be fine, as long as the frame is grounded (which it is).
It should be possible to check each of the alarm circuits individually?
From the wiring diagram, there appears to be just the following five sensor circuits:
Doors (Connector 2, pin 21) - tripped if grounded (pin switch is closed when door opens)
Hood (Connector 2, pin 5) - tripped if grounded (pin switch is closed when hood opens)
Hatch (Connector 2, pin 3) - tripped if grounded (pin switch is closed when hatch opens)
Glove box (Connector 2, pin 16) - tripped if grounded
Radio (Connector 2, pin 9) - tripped if ground DISconnected
I'm not sure what terminal 15, 30, and 61 are. I guess that terminal 30 is +12v and terminal 15 is accessory. Terminal 61 attaches to the ignition control (EZK?), which I would assume is an engine disable output.
My passenger seat is off and I've got complete access to the alarm module. I'm going to test my thinking with the sensor circuits.
10-14-2012, 07:40 PM
#11
Electron Wrangler
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30 is battery direct, 15 is ignition, 31 is ground, 61 is an alternator generating input ( e.g. ~ engine running). Disable ignition is on Pin 4 Connector 1 (quite different).
You have a hatch pin switch (trigger) and a hatch unlock (suspends the alarm until the hatch is closed again - does not unlock the doors). Radio1 trigger Brown (triggers on OC) & Radio 2 trigger is Brown/Yellow (seems it also triggers on OC from what you say - so must be two the same - odd - not sure on this)...
Radio 1 is usually just left permanently grounded at the cigar lighter/power outlet (one of 2 very small grounds there). Try just grounding the brown/yellow wire for now.
Alan
You have a hatch pin switch (trigger) and a hatch unlock (suspends the alarm until the hatch is closed again - does not unlock the doors). Radio1 trigger Brown (triggers on OC) & Radio 2 trigger is Brown/Yellow (seems it also triggers on OC from what you say - so must be two the same - odd - not sure on this)...
Radio 1 is usually just left permanently grounded at the cigar lighter/power outlet (one of 2 very small grounds there). Try just grounding the brown/yellow wire for now.
Alan
