question on 4 wheel drive
Thread Starter
|
Beginning Member
Joined: Jan 2015
Posts: 15
question on 4 wheel drive
Hi I have a1998 Chevy blazer and I have replaced the tccm the front axle sensor and the 4 wheel drive switch on the dash and the vacuum accuater under the battery try and all it does is says it is in 4hi on the switch and when I try 4lo or 2hi it just clickes at the tccm and goes back to 4hi any help thank you mike
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
Only a couple of more parts to go 
Encoder motor and vacuum switch, both are on the transfer case. Have you checked both terminals on all fuses in both fuse panels with a test light or volt meter?
Encoder motor and vacuum switch, both are on the transfer case. Have you checked both terminals on all fuses in both fuse panels with a test light or volt meter?
Thread Starter
|
Beginning Member
Joined: Jan 2015
Posts: 15
Do you know what two fuses they are and what will it say on the fuse box I reset the tccm like the one web site said I just took the fuse that said 4 WD in the dash fuse box out water a half hour and put it back in and turn the key to the on position and wited until the lights went off and cycled the key five times like it said is there one that controls the 4 WD in the fuse box under the hood it also blinks when I try to put it in 2 WD or 4 lo but I do her the enctor motor engaging so what els can it be thank you mike
Last edited by monkey23; Apr 12, 2015 at 03:16 AM. Reason: misspelled a word
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
There are 5 fuses for the 4WD system.
In the instrument panel fuse panel:
4WD fuse #15 10amp must show battery voltage in the RUN position.
CTSY LP fuse #8 10 amp must show battery voltage at all times.
In the underhood fuse panel:
ATC fuse 20 amp must show battery voltage at all times.
BTSI fuse 10 amp must show battery voltage in PARK & NEUTRAL.
CRANK fuse 10 amp must show battery voltage in the START position.
Do not remove the fuses while testing. Test both terminals on the top of each fuse.
Post your results.
In the instrument panel fuse panel:
4WD fuse #15 10amp must show battery voltage in the RUN position.
CTSY LP fuse #8 10 amp must show battery voltage at all times.
In the underhood fuse panel:
ATC fuse 20 amp must show battery voltage at all times.
BTSI fuse 10 amp must show battery voltage in PARK & NEUTRAL.
CRANK fuse 10 amp must show battery voltage in the START position.
Do not remove the fuses while testing. Test both terminals on the top of each fuse.
Post your results.
Thread Starter
|
Beginning Member
Joined: Jan 2015
Posts: 15
fuse check
Hi just did the fuse check and the 4wd fuse has battery voltage in the run position on both sides ctsy lp has battery voltage on both sides at all times ATC fuse has battery voltage all the time btsi fuse has no battery voltage at all the crank fuse has no battery voltage at all
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
BTSI fuse 10 amp must show battery voltage in PARK & NEUTRAL with the ignition in the RUN position. Is that how you tested it? (sorry, I wasn't real clear on that one)
CRANK fuse does not show battery voltage in the START position? Is that correct?
CRANK fuse does not show battery voltage in the START position? Is that correct?
Thread Starter
|
Beginning Member
Joined: Jan 2015
Posts: 15
fuse check four wheel drive
The crank fuse has no battery voltage at all on start I will recheck the btsl fuse later today I thought the car had to be running to check that one and I will post the results again
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
The CRANK fuse gets power from the ignition switch. Connector "D" pin #1. Trace it back from the underhood fuse panel to the ignition switch to locate & repair the problem. It feeds the transfer case control module and the transmission range switch located on the transmission.