Trouble starting Trailblazer
Trouble starting Trailblazer
Hey guys, got a friend of mine(trying to get her on here btw) that is having an issue that I could use a little help on.
Not sure of the year but know it's a 2nd gen Trailblazer. And she's having some issues with it starting lately.
She's just put in a brand new battery within the last month, and the alt was checked to be fine. Her most recent statement:
"when i turn it on the voltage is close to 9 then after a few seconds it realizes that it is running and it will jump up to 14 and when it warms up it sets at 17. It starts fine, it is just like the memory is not catching up and it is worse the colder it is. My next thing to check is the connectors"
Maybe a belt issue?
Anyone have any additional ideas, other than the wiring which she is going to check? She lives about an hour from me, so not too easy to go see the truck myself right now.
Not sure of the year but know it's a 2nd gen Trailblazer. And she's having some issues with it starting lately.
She's just put in a brand new battery within the last month, and the alt was checked to be fine. Her most recent statement:
"when i turn it on the voltage is close to 9 then after a few seconds it realizes that it is running and it will jump up to 14 and when it warms up it sets at 17. It starts fine, it is just like the memory is not catching up and it is worse the colder it is. My next thing to check is the connectors"
Maybe a belt issue?
Anyone have any additional ideas, other than the wiring which she is going to check? She lives about an hour from me, so not too easy to go see the truck myself right now.
Just to clarify the vehicle in question, does it look similar to yours, but with different rims, rocker skirts, embroidery on the seats, etc? Or are you talking about the newer GMT360 platform vehicles?
On the GMT360 vehicles with the 4200 I6 engine, the alternator can go through wicked swings in output if the vehicle is not allowed to run it's start-up AIR (air injection reaction) pump test. This is commonly noticed when slowing down and can be enough to cause the vehicle to stall out (not nice when coming up to a turn or pulling into a parking lot on a busy road).
With the s-series trucks, there can sometimes be a problem with either the wiring between the PCM & the alternator that can cause inconsistent output from the alternator. The stock wiring is setup such that the PCM controls the output. The alternator can be rewired to the older style of reference voltage control and that typically cures the wild swings provided that the alternator is working properly. There is a thread in the Tech Article (DIY) Index (link in my signature) that explains how to convert the alternator from PWM (pulse width modulated) control to voltage reference.
On the GMT360 vehicles with the 4200 I6 engine, the alternator can go through wicked swings in output if the vehicle is not allowed to run it's start-up AIR (air injection reaction) pump test. This is commonly noticed when slowing down and can be enough to cause the vehicle to stall out (not nice when coming up to a turn or pulling into a parking lot on a busy road).
With the s-series trucks, there can sometimes be a problem with either the wiring between the PCM & the alternator that can cause inconsistent output from the alternator. The stock wiring is setup such that the PCM controls the output. The alternator can be rewired to the older style of reference voltage control and that typically cures the wild swings provided that the alternator is working properly. There is a thread in the Tech Article (DIY) Index (link in my signature) that explains how to convert the alternator from PWM (pulse width modulated) control to voltage reference.
Just to clarify the vehicle in question, does it look similar to yours, but with different rims, rocker skirts, embroidery on the seats, etc? Or are you talking about the newer GMT360 platform vehicles?
On the GMT360 vehicles with the 4200 I6 engine, the alternator can go through wicked swings in output if the vehicle is not allowed to run it's start-up AIR (air injection reaction) pump test. This is commonly noticed when slowing down and can be enough to cause the vehicle to stall out (not nice when coming up to a turn or pulling into a parking lot on a busy road).
With the s-series trucks, there can sometimes be a problem with either the wiring between the PCM & the alternator that can cause inconsistent output from the alternator. The stock wiring is setup such that the PCM controls the output. The alternator can be rewired to the older style of reference voltage control and that typically cures the wild swings provided that the alternator is working properly. There is a thread in the Tech Article (DIY) Index (link in my signature) that explains how to convert the alternator from PWM (pulse width modulated) control to voltage reference.
On the GMT360 vehicles with the 4200 I6 engine, the alternator can go through wicked swings in output if the vehicle is not allowed to run it's start-up AIR (air injection reaction) pump test. This is commonly noticed when slowing down and can be enough to cause the vehicle to stall out (not nice when coming up to a turn or pulling into a parking lot on a busy road).
With the s-series trucks, there can sometimes be a problem with either the wiring between the PCM & the alternator that can cause inconsistent output from the alternator. The stock wiring is setup such that the PCM controls the output. The alternator can be rewired to the older style of reference voltage control and that typically cures the wild swings provided that the alternator is working properly. There is a thread in the Tech Article (DIY) Index (link in my signature) that explains how to convert the alternator from PWM (pulse width modulated) control to voltage reference.
Should be the S-series, I do remember reading about that post the other day, when someone else was having alternator issues. Thanks for the tip, I'll send her the link to this thread, and maybe she just might find a reason to join in on the fun!
Thread
Thread Starter
Forum
Replies
Last Post
dcjones
2nd Generation S-series (1995-2005) Tech
6
Jan 19, 2006 10:54 PM
