QuestionQUESTION: The battery on my 91 LeBaron Convertible LX drains after a few days. Using your advice to another questioner, I pulled the fuses and relays under the hood and checked for current flow with an ammeter as I replaced them. Current flow was negligible until I replaced either one of two fuses: FUEL SYS ELECT TRANS (30A) or HDT REAR WIND (50A). Either one caused the ammeter to peg beyond the 250mA scale. Then I disconnected the rear window defrost and pulled the fuel pump relay, but neither one reduced the current flow. I don’t think either one of these circuits should be hot with the ignition off, so my guess is that there is a short that involves these two systems or there are other items on the fuses that are causing the drain. Another issue that may or may not be related is that the headlight switch is sometimes intermittent and the lights just go off while driving. I would appreciate any ideas on what to do next.
ANSWER: Hi Jim,
I would go a little bit further on pulling fuses/devices. For the 50A fuse, it feeds fuse 26 (10 Amp) under the dash which feeds all the always available lights:reading, courtesy, trunk, intrument cluster, radio memory presets, trip computer, and body computer. I would check those beginning with trunk and glove box lights and work your way up from there to the harder to access.
On the 30 Amp fuse it feeds the engine controller, autoshutdown relay, and thru the ASD to the transmission shutdown relay. I suspect that your ASD may be stuck closed, so trying pulling that and measure across from 27 to 29 (which are connected to red/white and dark green/black wires) to see if the contacts are welded together.
Let me know if you have a 2.5 or a 3.0L if you write back. The ASD is in the underhood box you have been looking at already.
Roland
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QUESTION: It's a 3.0L. Pulling the 10A #26 fuse solved half the problem... I just need to track it down to specific item. I still have a drain through the 30A FUEL SYST ELECT TRANS fuse. I could not find a relay marked ASD. I pulled all 7 relays (RADIATOR FAN, AIR COND CLUTCH, 3 HEADLIGHT MOTORS, FUEL PUMP and STARTER) in the power distribution center box and it did not reduce the drain. Is the ASD relay somewhere else? Other ideas? Thanks.
ANSWER: Hi Jim,
The "fuel pump relay" is in fact the ASD relay. There is one other relay on that fuse, the transmission shutdown relay. The wiring diagrams says its on the left fender shield, so try pulling that one also. How much current is still being drawn thru that 30 Amp fuse? The engine and trans controllers both draw some current even when not in use, so that may be what you are seeing there. I would solve the #26 draw issue first. Make sure that you don't have any lights on unknowingly.
Roland
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QUESTION: Roland,
Could not find a trans shutdown relay, but the current through that 30A fuse is only 0.03A according to my large scale ammeter. Is that an acceptable drain? You are correct in that the biggest drain is through the #26 fuse at 0.14A. I went through all the lights and pulled the radio fuse with no change in drain. I am considering pulling the radio since it is an after market radio and may be the culprit. Your thoughts? Thanks for your help.
AnswerPS The 0.03 mA is fine. Yes, see what the decrease is when you disconnect the radio completely. The #26 is needed for the internal memory of that. But if you are driving it fairly regularly, I don't believe an extra 0.1 mA will discharge the battery.
Roland
Hi Jim,
I don't believe that is such a high off-draw as to drain the battery down unless you are going to be storing the car for a month. So see what you experience. Or measure the draw with the radio unhooked. Let me know what remains and we can look at the other items.
Roland
