This month, we survey OEM TSBs for known problems in vehicle charging and starting systems. Our roundup encounters a variety of issues on several different makes and models:
– The potential for shorting out the TCM when jump starting certain GM models
– Lexus models with disabled starting function after battery charging or jump starting
– Starting issues on Scions equipped with remote start systems
– Swapped subwoofer connections causing parasitic drains on Volvo S80, V70 and VC70 models
– Honda Civic battery drains caused by owner driving habits
GM – Risk of TCM Shorting Due to Contact with Positive Battery Post
In this TSB, GM warns of the potential to short the Transmission Control Module (TCM) while jump starting, as well as the risk of shorting the TCM during other repair activities. Several suggestions are provided to reduce the chance of this happening. This TSB relates to several GM vehicles as identified in the TSB, just click the image below to read more:
Lexus – Severely Discharged Battery Causing Steering Lock ECU Hangup
In this TSB, Lexus identifies an issue that can arise when battery voltage drops below 9V. When this happens, the customer or service facility typically recharges the depleted battery or jump starts the vehicle. But, the discharge battery can cause a condition in the Steering Lock ECU that requires it to be re-initialized. Several Lexus models are affected and this TSB provides the recommended re-initialization procedure: https://www.lexustsb.com/questions/181/TSIB+EL016-06+VEHICLE+START+AFTER+BATTERY+DEPLETION
Scion – Severely Discharged Battery Caused by Remote Start System
In this TSB, Scion identifies an issue on xB and xD models equipped with Remote Start Systems. On these models, the Remote Start System can create a parasitic drain that results in a discharged battery condition after short term storage. This TSB explains the procedure to determine if the Remote Start System is the cause of excessive parasitic drain:
Volvo – Severely Discharged Battery Resulting from Swapped Connection
More excessive parasitic drains. On Volvo S80, V70 and VC70 models equipped with Active Suspension and Subwoofer prep, excessive battery drain will result if the SUM (SUspension Module) and the prewired SUB (SUBwoofer) are swapped. The SUM will remain active and the current draw will be approximately 80-400 mA and the vehicle will not go into sleep. The connectors for SUM and SUB are in close proximity to one another and are physically interchangeable. This TSB identifies the proper connections, which when followed, will resolve the issue:
Honda – Severely Discharged Battery Resulting from Driving Habits
On certain Honda Civic and CRV models, owners encounter a dead battery after the vehicle has sat idle for as little as two days, resulting in the need for multiple jump starts. This condition can have a number of causes, including excessive battery sulfation and owner driving habits, and is typically related to a failure of the PCM to select the correct charging mode for the vehicle. This TSB identifies the specific models affect and the corrective action to take (TSB in Post #6):
Wow. Many system issues related to excessive drain. Not a huge surprise, considering the number of articles and instructional videos published by industry publications related to diagnosing and addressing parasitic drains. And, watch out for that GM issue related to the TCM. All Clore Automotive jump starters now feature non-metal clamps for this reason, among others. We want to help you avoid costly inadvertent shorts. We hope that you finds these TSBs useful.
