Low voltage to pcm and injector fuses? - Chevy Impala SS Forum
 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 10-05-2018, 10:58 AM Thread Starter
Senior Member
 
babywag's Avatar
 
Join Date: Mar 2016
Location: California
Posts: 975
 
Low voltage to pcm and injector fuses?

I searched but did not find exact issue mentioned.
Yesterday I was checking some things out and found that all 4 fuses for engine management are much lower than everything else.
They're all ~12v when the engine is running, but everything else is ~14v.
So the pcm, maf, coil, icm, injectors, o2 sensors and trans. are all only getting 12v.
Seems odd to me, is this a known issue/problem on a 1994?
These dudes...
babywag is offline  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 10-05-2018, 12:58 PM Thread Starter
Senior Member
 
babywag's Avatar
 
Join Date: Mar 2016
Location: California
Posts: 975
 
Agh...found the problem.
Ignition switch output 13.9v to aftermarket alarm module.
Coming OUT from the unit is only 12.7v and it fluctuates slightly as well.
@ underhood fuse unit, it's a little lower which would be normal for the length of the wire run.

The installer did a decent job, the loss is from the control module itself.
Ah the joys of aftermarket products
babywag is offline  
post #3 of 4 (permalink) Old 10-06-2018, 01:22 PM
Senior Member
 
Join Date: May 2001
Location: Southeast Michigan
Posts: 359
 
Is the control module grounded properly?

Ken
Ken Hennessy is offline  
 
post #4 of 4 (permalink) Old 10-06-2018, 01:44 PM Thread Starter
Senior Member
 
babywag's Avatar
 
Join Date: Mar 2016
Location: California
Posts: 975
 
Quote:
Originally Posted by Ken Hennessy View Post
Is the control module grounded properly?

Ken
Yes, it was grounded well.
Less than an ohm when checked to multiple locations.
Even put a jumper on it to test.
Still huge voltage loss so I bypassed the turd and problem solved.
Rock solid 13.6 @ fuses now.

The low voltage would very likely explain some intermittent oddities I could never figure out.
babywag is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala SS Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome