Alternate Measure Passlock? Why cant get I my bypass to work with Passlock? Why is the resistance always changing? I set the resistance correctly but it still doesnt work- What can I do?
Some meters have problems measuring Passlock Systems. It does not matter how much the meter cost- any meter can have the problem.
If you are having trouble setting up your bypass module, such as getting a different resistance every time, no resistance, or the vehicle just wont work regardless of the resistance, this is the next step to test---
There is another way you can dial in your measurement, although it is NOT SUPPORTED:
One wire will have 0 volts- This is the wire you "tap" into-- we'll call this WIRE #1 (usually BLACK or ORANGE / BLACK)
One wire will have 5 volts or less- This is the wire you cut in half-- we'll call this WIRE #2 (usually YELLOW)
One wire will have about 12 volts- This is the wire you leave alone
- With all PASSLOCK wires intact, turn the vehicle on and bump the starter. Measure the voltage between the wire #1 and wire#2. Your meter should be set on the 12 volt DC scale. RECORD THIS VOLTAGE.
- Without turning the key off go ahead and separate WIRE#2. Reconnect the Universal Alarm Bypass Module as described in the installation manual for the 20401/20402 with one exception- GROUND the the wires that go to ignition 3. When you ground this wire you should hear the bypass module click.
- Now measure the voltage between the ENGINE side of WIRE#2 and wire#1. Your meter should be set on the 12 volt DC scale.
- "Play" with the dipswitches and trim pot on the bypass module until the voltage being measured EXACTLY matches the recorded voltage from above.
When you remove ground from the ignition 3 wire of the bypass module the voltage should NOT change. Reapply ground to verify- If you get the same voltage every time then the module is set up PERFECTLY!
There is no chart to help you with this, it is just trial and error-- but it will work regardless of the brand meter you are using...
another way to get an acurate reading is set the park brake slip car into reverse and then turn key to start you can hold it there as long as you want to get a true reading.
Voltage is the best way to do it. I have been using the voltage method for years and have never had any problems other then faulty modules.
exactly Player, this is about voltage not resistance.
Lately I've been using the data bypasses. So far, so good. It's nice knowing that there won't be any resistance changes down the road. I highly recommend this route.