Dim fuel low light - instrument cluster issue

W4UWC

New Member
I've read a lot about "dim lights". Most of the search results were related to LED installs. I've seen ignition switches and new batteries and alternators as a possible cause. In this case it is definitely in the cluster.

The fuel light stays dim with the key off. It illuminates bright when the start sequence happens then remains dim once the vehicle is running. I haven't driven the vehicle enough to see if it comes on when the fuel is actually low. I put the cluster in another Envoy and it did the same thing so it rules out anything outside the cluster. Here is a pic of both conditions.

My question is if anyone has seen this and if so could it be repaired? I haven't split the cluster open to see if there is anything obvious.

Thanks in advance for the help!

2004 Envoy XL SLT 4.2L
 

Attachments

Mooseman

Moderator
OP
OP
W4UWC

W4UWC

New Member
I swapped another cluster that is good but it has a lot more miles so I'd live with the dim light vs high miles I do need to verify that light which is on continuously won't drain the battery
 

budwich

Well-Known Member
if you got the cluster out, then take a meter and do some electrical resistance measurements based on the cluster electrical schematics.... may guess at this point, is that there may be a "slight ground" or possible a faulty transistor... maybe and no I haven't pull up the schematics at this point.
 

budwich

Well-Known Member
:-(... the bad news... based on the schematic (which isn't that good in this area), the indicators are lit as part of "serial logic" and thus "discreet test points" might be hard to come by. If you post a "good picture" of the panel and the area in question "low fuel", we might be able to provide the guidance based on "visual clues" from the board / panel. Based on the limited info in the manual, the indicator is some form of LED... the power is always provided (IGN) so what ever form of "logic" passes some form of ground (switch or otherwise)... if there are discreet elements in the area, you might be able to check those and / other connections there in. The "serial logic" suggests some form of switching transistor... that may be "leaking".
 

Mooseman

Moderator
If draining the battery with the old cluster is worrying you, you could do a parasitic draw test.
 
OP
OP
W4UWC

W4UWC

New Member
Thanks so much! This truck has transmission issues and I've driven it maybe 1/4 mile so while I'm investigating that I'm also looking at other systems and learning what else needs attention. That dim fuel light was odd. I'm not concerned it will drain the battery as it's a low priority. I appreciate the replies and agree with Budwch that it needs to be opened and then visually and electrically checked. I'm betting it's a ground problem. That'll come with time. Since the fix isn't obvious then it'll be on the growing list of to-dos.

Thanks again. I'm glad I kind of stumped the experts with an unusual question!
 

Online statistics

Members online
4
Guests online
230
Total visitors
234

Members online

Forum statistics

Threads
19,801
Messages
585,401
Unanswered questions
2
Answered questions
1
Members
12,558
Latest member
Nate Saxby
Top Bottom