dash gages going to zero and radio turning off
09-29-2017 | 05:53 PM
#11
Moderator
Joined: 05-01-2014
Posts: 8,174
From: California
My daughter brought the car home today. On her way home, it acted up 4 times. Three were quick blips and 1 was longer. Engine ran fine. After she came home, she took the car to the store, and it ran fine to the store. However, it wouldn’t start on the way home. She turned the key and the dash came on, but no solenoid click. It eventually started and she made it home (5-10 minute drive).
When she got home, I had her keep the car running, and I looked at the dash and it was dead for many seconds, and eventually came back to life.
I looked quickly for the chaffing wire locations and did see and contact, but I have to inspect more.
I measured the charging voltage it was 14.9 – 15.0 volts (at the engine fuse box) which I thought was high. I cycled the AC and other loads and the voltage didn’t change. With the car off, the battery voltage was about 12.6 volts.
I have a new alternator, serpentine belt tool, and belt, and I plan on changing the alternator tomorrow morning.
Does this additional info change anyone’s mind or make you think there is another issue?
She is going back to school tomorrow afternoon, so I only have a small window to work on this.
When she got home, I had her keep the car running, and I looked at the dash and it was dead for many seconds, and eventually came back to life.
I looked quickly for the chaffing wire locations and did see and contact, but I have to inspect more.
I measured the charging voltage it was 14.9 – 15.0 volts (at the engine fuse box) which I thought was high. I cycled the AC and other loads and the voltage didn’t change. With the car off, the battery voltage was about 12.6 volts.
I have a new alternator, serpentine belt tool, and belt, and I plan on changing the alternator tomorrow morning.
Does this additional info change anyone’s mind or make you think there is another issue?
She is going back to school tomorrow afternoon, so I only have a small window to work on this.
09-29-2017 | 06:05 PM
#12
Moderator
Joined: 01-23-2009
Posts: 25,339
From: Fredericksburg,VA
I don't think alternator is bad. If you are thinking of using a standard belt tool, good luck. Why would you think 14.9-15 is high? Plus, keep in mind these new-fangled cars have computer controlled regulators, not on/off like a '57 chevy.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
09-29-2017 | 07:11 PM
#13
Platinum Member
Joined: 12-06-2009
Posts: 11,432
From: Alabama
X2 on the alternator and charging voltage. Sounds fine to me by the HHR specs and repair manuals I've read.
Fwiw. One spec I recall reading is the alternator can put out as much as 19 volts under extreme loads.
Fwiw. One spec I recall reading is the alternator can put out as much as 19 volts under extreme loads.
09-29-2017 | 07:54 PM
#14
Thread Starter
New Member
Joined: 08-25-2012
Posts: 25
From: United States
I don't think alternator is bad. If you are thinking of using a standard belt tool, good luck. Why would you think 14.9-15 is high? Plus, keep in mind these new-fangled cars have computer controlled regulators, not on/off like a '57 chevy.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
https://itstillruns.com/output-volta...s-7754415.html
Quick Test: Faulty Alternators - Hot Rod Network
Last edited by ChevyHighPerformance; 09-29-2017 at 08:05 PM. Reason: spelling mistake
09-29-2017 | 07:59 PM
#15
Thread Starter
New Member
Joined: 08-25-2012
Posts: 25
From: United States
I plan to do everything everyone suggested. I knew I had a small window to work on this. So, I bought an alternator and belt that I can return if I need to. I'll can use the serpentine belt tool anyway.
I really do appreciate everyone's help. I have several things to try. I'm going to visually check for chaffing, then check for bad connections, then check the grounds, then see if I can get the battery and alternator tested, then if the alternator is bad - I'll change it.
I really do appreciate everyone's help. I have several things to try. I'm going to visually check for chaffing, then check for bad connections, then check the grounds, then see if I can get the battery and alternator tested, then if the alternator is bad - I'll change it.
09-29-2017 | 08:03 PM
#16
Thread Starter
New Member
Joined: 08-25-2012
Posts: 25
From: United States
I don't think alternator is bad. If you are thinking of using a standard belt tool, good luck. Why would you think 14.9-15 is high? Plus, keep in mind these new-fangled cars have computer controlled regulators, not on/off like a '57 chevy.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
Sounds more like a loose wire, like the large red one on the fuse box or the ground on the engine to the rad support.
I can actually get to the tensioner from the engine compartment.
09-30-2017 | 09:25 PM
#18
Thread Starter
New Member
Joined: 08-25-2012
Posts: 25
From: United States
Just an update:
Sorry for the long post again – I just wanted to list my steps in case anyone else has this problem.
I inspected each cable in the engine compartment (hand-over-hand) and no chaffing, and none were even not rubbing in the typical areas:
on the ECM/PCM case and/or on the edge of either ECM/PCM connector body
at the UBEC bracket
at the cylinder head plate (power steering pump blockout)
at the EVAP purge valve bracket
at the rear of the cylinder head/upper edge of transmission bell housing
I removed the ECM connectors, sprayed contacted cleaner on both mating halves of the contacts.
I read where someone’s OBD2 connector wires were chafed due to rubbing on some sharp metal and had communication issues. I re-inspected the wires (no chaffing), found the sharp edges, and I put plastic wire loom over the wires to protect them. I also fixed the sloppy work GM did when they did the steering motor recall.
I inspected the BCM wiring and found some chaffing where wires were rubbing over a metal bracket. It didn’t look like the insulation was cut through, but I put a piece of plastic wire loom over the wires anyway.
I started the car, and had someone sit inside and observe the tach and put the turn signal on. When the blip occurs, the tach drops suddenly and the turn signal audible cadence skips a beat. I wiggled all of the cables in the engine compartment and no hiccups. I wiggled one of the BCM cables and got it to hiccup. This was the vertical rectangular connector that connects to the side of the BCM near the shifter.
It was tough to repeat the hiccup. Sometimes I could get three blips in a row and sometimes nothing would happen. Previously, I sprayed contact cleaner on both halves on the contacts. I unlatched the connector and slowly moved the latch so it started to separate the contacts (I was hoping to see if a contact was just barely making a connection) – no hiccups. I removed the connector’s back shell, and wiggled each wire separately along with trying to pull out and push in – no hiccups.
I checked the pending trouble codes on all of the modules and nothing was stored even after several hiccups. I was expecting a pending U code. I then guessed that something could be wrong inside the BCM (bad solder joint, week trace, etc.).
I replaced the BCM and so far there wasn’t any issues when my daughter drove the car back to school (~45 minutes).
There’s not enough data to say if this fixed the problem. I’ll update this thread to bring some sort of closure.
I appreciate everyone’s input/suggestions on my issue!
Sorry for the long post again – I just wanted to list my steps in case anyone else has this problem.
I inspected each cable in the engine compartment (hand-over-hand) and no chaffing, and none were even not rubbing in the typical areas:
on the ECM/PCM case and/or on the edge of either ECM/PCM connector body
at the UBEC bracket
at the cylinder head plate (power steering pump blockout)
at the EVAP purge valve bracket
at the rear of the cylinder head/upper edge of transmission bell housing
I removed the ECM connectors, sprayed contacted cleaner on both mating halves of the contacts.
I read where someone’s OBD2 connector wires were chafed due to rubbing on some sharp metal and had communication issues. I re-inspected the wires (no chaffing), found the sharp edges, and I put plastic wire loom over the wires to protect them. I also fixed the sloppy work GM did when they did the steering motor recall.
I inspected the BCM wiring and found some chaffing where wires were rubbing over a metal bracket. It didn’t look like the insulation was cut through, but I put a piece of plastic wire loom over the wires anyway.
I started the car, and had someone sit inside and observe the tach and put the turn signal on. When the blip occurs, the tach drops suddenly and the turn signal audible cadence skips a beat. I wiggled all of the cables in the engine compartment and no hiccups. I wiggled one of the BCM cables and got it to hiccup. This was the vertical rectangular connector that connects to the side of the BCM near the shifter.
It was tough to repeat the hiccup. Sometimes I could get three blips in a row and sometimes nothing would happen. Previously, I sprayed contact cleaner on both halves on the contacts. I unlatched the connector and slowly moved the latch so it started to separate the contacts (I was hoping to see if a contact was just barely making a connection) – no hiccups. I removed the connector’s back shell, and wiggled each wire separately along with trying to pull out and push in – no hiccups.
I checked the pending trouble codes on all of the modules and nothing was stored even after several hiccups. I was expecting a pending U code. I then guessed that something could be wrong inside the BCM (bad solder joint, week trace, etc.).
I replaced the BCM and so far there wasn’t any issues when my daughter drove the car back to school (~45 minutes).
There’s not enough data to say if this fixed the problem. I’ll update this thread to bring some sort of closure.
I appreciate everyone’s input/suggestions on my issue!
Last edited by ChevyHighPerformance; 09-30-2017 at 09:31 PM. Reason: added DTC checking onfo