90 Renix Battery + Latch won't unlatch
#16
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Year: 1989
Model: Comanche (MJ)
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X2. The ground/power to the relay should be easy to check at the diagnostic connector, assuming the wiring is intact and not mucked up somewhere(which is my suspicion). I'd put a test light across those two pins in the diagnostic connector and see what it's doing, both with and without the relay installed.
#17
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Year: 1990
Model: Cherokee (XJ)
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I’ll try the test light across those pins. With regard to ohm readings I’m getting Zero from the relay sockets to those d2 test sockets.
with the ecu connected I get 2.2 M ohms from the relay ground and the d2 socket 3 to battery ground.
with the ecu disconnected I get an open circuit between relay ground and battery/chassis ground
will double check continuity of the relay ground to ecu pin. Ok that’s reading .2 ohms.
weird, now with a light across the d2 ports it lights up on key-on for a few seconds, then shuts off. with and without the relay plugged in.
With the relay in I am getting 10.7 bolts at the output pin. Top one 87. Which I suppose is normal. Upon key off it drops to 0.12 Vdc immediately Without the bulb across the d2 pins it slowly drops from about .5 volts to zero over twenty seconds or so.
this is sounding more normal?? I do have a different ecu connected
And now… with the nick in time code reader connected I get this:
key on. Pin 87 on relay sees 12.2 vdc
vide reader reads error “battery + latch open”
key off. Pin 87 stays latched at 12.2 vdc
unplug the code reader and pin 87 drops to .9 vdc then slowly falls to zero. Normal right??
could it have been this silly reader all the time?
not silly, it really works well for everything else, but…
this of course boils down to you suggesting the light across the d2 ports, thus forcing me to disconnect the reader. So, I think that’s a fix!!!!
so, many thank you’s for sticking with this !!
mark
with the ecu connected I get 2.2 M ohms from the relay ground and the d2 socket 3 to battery ground.
with the ecu disconnected I get an open circuit between relay ground and battery/chassis ground
will double check continuity of the relay ground to ecu pin. Ok that’s reading .2 ohms.
weird, now with a light across the d2 ports it lights up on key-on for a few seconds, then shuts off. with and without the relay plugged in.
With the relay in I am getting 10.7 bolts at the output pin. Top one 87. Which I suppose is normal. Upon key off it drops to 0.12 Vdc immediately Without the bulb across the d2 pins it slowly drops from about .5 volts to zero over twenty seconds or so.
this is sounding more normal?? I do have a different ecu connected
And now… with the nick in time code reader connected I get this:
key on. Pin 87 on relay sees 12.2 vdc
vide reader reads error “battery + latch open”
key off. Pin 87 stays latched at 12.2 vdc
unplug the code reader and pin 87 drops to .9 vdc then slowly falls to zero. Normal right??
could it have been this silly reader all the time?
not silly, it really works well for everything else, but…
this of course boils down to you suggesting the light across the d2 ports, thus forcing me to disconnect the reader. So, I think that’s a fix!!!!
so, many thank you’s for sticking with this !!
mark
#18
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Year: 1989
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Once we started talking about the diagnostic connector, I wondering if you had a REM connected to it. I suspect the REM uses the B+ pin to power itself.
Last edited by lawsoncl; 12-12-2021 at 01:51 PM.
#19
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Year: 1988
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So in hindsight, I have to ask (as I didn't see it in the thread), what was the original issue/symptom that lead you to the B+ Latch? And is that fixed now?
I don't have a REM but I think Nickintime would have accounted for it.
Looking at the DC pinouts, Pin 4 is the ign switch power, I'd guess this powers the REM.
I don't have a REM but I think Nickintime would have accounted for it.
Looking at the DC pinouts, Pin 4 is the ign switch power, I'd guess this powers the REM.
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