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Weird relay cycling possibly killing battery

  • Thread starter Thread starter Slatco
  • Start date Start date Jan 9, 2010

Slatco

New Member
Jan 9, 2010
29
1
3
Jan 9, 2010
#1
  • Jan 9, 2010
  • #1
Hey, just bought a 89 LX that needs to be charged everytime I go to start it. I think the issue is related to a relay that I can hear cylcling (even with the key off) Ive isolated the relay in a box that is mounted waayyyyy underneath the dash (behind a plastic protector/carpet underlay) I cant even see this box by laying upside down with the back of the clutch pedal in my mouth. I can only feel it.

I've determined that the relay cycles during the following conditions.
1. When I first turn the key forward to power everything up. If the driver door is open, I hear the warning chime, but it is at a different frequency than this chattering relay(it almost sounds like the same frequency as the hazard lights, but they work fine. You can turn them on and off regardless of what the realy is doing) Closing the door silences the chime but I still hear the click, click, click of the relay. This continues even if I remove the key.

2. The relay eventually stops (which leads me to believe it is on a timer) however, if I turn on the interior light using the dimmer control, or open either the passenger or driver door it will begin cycling again.

3. I installed a new battery and when I connected the negative, it arced on the terminal (indicating a load was present) and I could hear the relay again. (this was with the doors closed, interior light off and key out) I listened to it for a bit and it timed out.

Other than that the car idles fine and runs great. I have a Fluke multimeter and will monitor the drain on the battery with the car off and key out tommorrow.

Suggestions?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jan 9, 2010
#2
  • Jan 9, 2010
  • #2
You might find that it's the parking light relay for an alarm system.
 

Slatco

New Member
Jan 9, 2010
29
1
3
Jan 10, 2010
#3
  • Jan 10, 2010
  • #3
Thanks, that sounds right given the difficulty of accessing the box/module. Ive got a little camera borescope that I m going to use to take a look and if the relay box is not OEM it's outta there.
 

Slatco

New Member
Jan 9, 2010
29
1
3
Jan 11, 2010
#4
  • Jan 11, 2010
  • #4
Well the culprit turned out to be a Python 1000 car alarm which i removed and the clicking relay went away. However, I still have an issue as the electrical system is drawing 8 amps with nothing visible on. I troubleshot this to fuse location number 8, and when I removed it the draw went away. (I guess Ill need to investigate this further.)

Additionally, after removal of the Python alarm, I now have no headlights or interior lights (regardless if fuse number eight is in or out) I suspect I disconnected a common ground when I removed the alarm but I don't know which wire.

Does anyone have a installation schematic for a DEI Python 1000?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jan 11, 2010
#5
  • Jan 11, 2010
  • #5
8 amps is huge. I guess I'd start with the PW portion of the circuit.

How was the old alarm tied into your lighting system? Were there solder tees or tee-taps? If it was solder tees, you might have accidentally opened all 3 branches of the connection.

I'd test things at the back of the headlight switch. You can chase it forward from that point. It's easy to access headlight power and dimmer power terminals there.
 

Slatco

New Member
Jan 9, 2010
29
1
3
Mar 12, 2010
#6
  • Mar 12, 2010
  • #6
Finally got around to troubleshooting my headlight issue. Thanks Hissin50 for telling me where to start. I had pulled the dash originally to find the alarm module, and sure enough did not press in the connector for the headlight switch far enough. Lucky for me it was the first thing I checked.

Moral of the story, eliminate the simplest stuff first when troubleshooting.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 12, 2010
#7
  • Mar 12, 2010
  • #7
Hissin's a sharpe guy. Good job.
 
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