wires on replacement thermal actuator

[bubs71]

The four wheel drive quit working on my 1993 K1500. After checking the truck over and doing some research, I determined that I needed to replace the actuator. Apparently the factory actuator was a problem on these year/model trucks. I purchased one from a local dealership, but it did not come with instructions. There is an extra brown wire that was not on the old one. Anyone know what this wire should be connected to?

[Fireplug]

what color are the wires

[gearclash]

Originally Posted by bubs71

The four wheel drive quit working on my 1993 K1500. After checking the truck over and doing some research, I determined that I needed to replace the actuator. Apparently the factory actuator was a problem on these year/model trucks. I purchased one from a local dealership, but it did not come with instructions. There is an extra brown wire that was not on the old one. Anyone know what this wire should be connected to?

Here is a post I found elsewhere on the boards here. It refers to a GM tech service bulletin.

SLOW OR NO ENGAGEMENT OF FRT. AXLE WHEN 4WD IS SELECTED
#76-43-01A - (09/18/1998)
REVISION: 09/17/98 DIVS INVL 1 5 7

THIS BULLETIN IS BEING REVISED TO ADD INFORMATION TO THE SERVICE PROCEDURE, ADD A NEW PART NUMBER, AND INCLUDE SCHEMATICS. PLEASE DISCARD CORPORATE BULLETIN NUMBER 76-43-01 (SECTION 4 - DRIVE AXLE). __________________________________________________ ____________________

SUBJECT: SLOW OR NO ENGAGEMENT OF FRONT AXLE WHEN 4WD IS SELECTED (REPLACE FRONT AXLE ACTUATOR)

MODELS: 1988-97 CHEVROLET AND GMC K MODELS EXCLUDING 1988-93 MODELS OVER 8500# GVW

CONDITION:

SOME OWNERS MAY COMMENT THAT THE COLDER THE OUTSIDE TEMPERATURE IS, THE LONGER IT TAKES FOR THE FRONT AXLE TO ENGAGE WHEN 4 WHEEL DRIVE IS SELECTED, OR THE FRONT AXLE DOES NOT ENGAGE.

CAUSE:

THE FRONT AXLE ENGAGEMENT ACTUATOR IS A THERMALLY ACTIVATED COMPONENT. BECAUSE OF THIS CHARACTERISTIC, THE TIME REQUIRED FOR THE ACTUATOR TO COMPLETE 4 WHEEL DRIVE ENGAGEMENT IS EXTENDED AS THE TEMPERATURE DROPS.

CORRECTION:

REPLACE THE FRONT AXLE ACTUATOR AND INCLUDE THE APPLICABLE WIRING HARNESS KIT. REFER TO THE PARTS INFORMATION IN ORDER TO DETERMINE WHICH WIRING HARNESS KIT IS NEEDED.

1996 MODEL TRUCKS WITH A BUILD DATE ON OR AFTER JANUARY 2, 1996 ARE CONSIDERED AS "96I". IF THE BUILD DATE OF THE TRUCK IS UNKNOWN, VERIFY THE 3 CHARACTER "AXLE CODE" ON THE FRONT AXLE LABEL IN ORDER TO DETERMINE WHICH WIRE HARNESS TO ORDER.

THIS NEW ACTUATOR USES A MOTOR TO ENGAGE THE FRONT AXLE AND IS NOT AFFECTED BY TEMPERATURE. ON 1988-93 MODELS WITH A GVW RATING OVER 8500#, THE NEW ACTUATOR CANNOT BE INSTALLED AND THE THERMAL ACTUATOR WILL REMAIN THE SERVICE PART.

SERVICE PROCEDURE

1. REMOVE THE FRONT DIFFERENTIAL CARRIER SHIELD, IF EQUIPPED.

2. IF NECESSARY, CLEAN THE AXLE HOUSING IN THE AREA AROUND THE EXISTING ACTUATOR. DISCONNECT THE ACTUATOR'S ELECTRICAL CONNECTION AT THE FRONT AXLE HOUSING.

3. REMOVE THE FRONT AXLE ACTUATOR BY UNTHREADING THE ACTUATOR FROM THE AXLE HOUSING.

4. INSTALL THE SPACER FROM THE WIRING KIT INTO THE AXLE TUBE WITH THE FLAT SIDE SEATED AGAINST THE SHIFT FORK.

5. INSTALL THE ACTUATOR MOTOR AND TIGHTEN UNTIL THE SHOULDER OF THE ACTUATOR SEATS AGAINST THE AXLE TUBE.

IMPORTANT: IF BINDING OCCURS BEFORE THE ACTUATOR IS SEATED, REMOVE THE ACTUATOR AND RESEAT THE SPACER BY PUSHING ON THE SPACER WITH A SCREWDRIVER. THEN REINSTALL THE ACTUATOR.

ON K3 MODELS WITH THE CAST IRON AXLE TUBE, THERE MAY BE A CASTING BURR WHICH MAY CONTACT THE EDGE OF THE ACTUATOR. THIS SHOULD NOT CREATE A CONCERN AND THE ACTUATOR SHOULD SEAT AGAINST THE AXLE TUBE. IF THIS CONTACT REMAINS A CONCERN, USE A DIE GRINDER IN ORDER TO REMOVE THE BURR.

6. CONNECT THE SERVICE HARNESS CONNECTOR TO THE ACTUATOR AND CONNECT THE 2-PIN CONNECTOR TO THE MATING CONNECTOR AT THE AXLE. FOR 1994 TO CURRENT MODELS, IN THE CASE OF A COMPLETE AXLE REPLACEMENT, REFER TO FIGURE 1.

7. ROUTE THE WIRING HARNESS ALONG THE EXISTING HARNESS ON THE RIGHT SIDE OF THE VEHICLE. ROUTE CKT 241 (BRN) OVER THE TOP AND TO THE LEFT OF THE TRANSMISSION. SECURE THE HARNESS USING PLASTIC TIES.

8. FOR 1995-97 INTERIM VEHICLES, LOCATE THE 4-WIRE CONNECTOR (C120) ON THE LEFT SIDE OF THE TRANSMISSION. SPLICE THE BRN WIRE OF THE ACTUATOR HARNESS INTO CAVITY D OF CKT 241 (BRN) ON THE ENGINE SIDE OF CONNECTOR C120. FOLLOW THE SPLICING PROCEDURE DESCRIBED IN SECTION 8A (ELECTRICAL DIAGNOSIS REPAIR PROCEDURES) OF THE APPLICABLE SERVICE MANUAL.

IMPORTANT: THE NEW FAST AXLE ACTUATOR REQUIRES ONLY 1 SPLICE. - FOR 1993 AND PRIOR VEHICLES, SPLICE INTO CKT 50 (BRN) BETWEEN CONNECTOR C152 AND GT101 (FIGURES 2,3,4). - FOR 1994 VEHICLES, SPLICE INTO CKT 50 (BRN) BETWEEN CONNECTOR C152 AND P101 (FIGURES 5,6). - FOR 1995-97 VEHICLES, SPLICE INTO CKT 241 (BRN) BETWEEN CONNECTORS C120 AND C100 (FIGURE 7).

NOTICE: CONNECTIONS MUST BE WATER TIGHT IN ORDER TO PREVENT WATER FROM ENTERING THE CIRCUIT AND CAUSING DAMAGE TO THE COMPONENTS.

9. ON K3 MODELS, INSTALL THE DELAY RELAY, INCLUDED AS PART OF THE WIRING HARNESS KIT, AT THE ENGINE SIDE OF THE BULKHEAD, ADJACENT TO THE EXISTING RELAY. MOUNT THE NEW RELAY WITH SELF-DRILLING FASTENER, P/N 22510339. ROUTE AND SECURE THE RELAY WIRE HARNESS BEHIND THE RIGHT OXYGEN SENSOR HEAT SHIELD.

10. VERIFY SYSTEM OPERATION. WHEN SHIFTING THE TRANSFER CASE, YOU SHOULD HEAR THE ACTUATOR MOTOR OPERATE.

IMPORTANT: THIS RELAY INCORPORATES A 5 SECOND DELAY FOR THE FRONT AXLE TO ENGAGE IN ORDER TO ALLOW THE TRANSFER CASE SYNCHRONIZER TO ENERGIZE.

FOR 88-93 VEHICLES, IF THE AXLE HAS TO BE REPLACED, USE JUMPER HARNESS P/N 15313272. CKT 1695 (BLK/WHT) FITS INTO CAVITY A OF THE FAST ACTUATOR. THE CIRCUIT INCLUDES THE CABLE SEAL AND THE TERMINAL PIN. THIS CIRCUIT PLUGS INTO THE 5-PIN AXLE ACTUATOR CONNECTOR.

11. DO THE FOLLOWING STEPS IN ORDER TO INSTALL JUMPER HARNESS P/N 15313272:

1. LOCATE THE AXLE ACTUATOR 5-PIN CONNECTOR ON THE SERVICE ACTUATOR WIRING HARNESS AND REMOVE THE TPA. 2. REMOVE AND DISCARD THE CAVITY PLUG FROM CAVITY A. 3. INSTALL CKT 1695 LEAD (BLK/WHT) FROM THE JUMPER HARNESS THAT HAS THE CABLE SEAL AND TERMINAL INTO AXLE ACTUATOR CONNECTOR CAVITY A. 4. REINSTALL THE TPA ON THE 5-PIN CONNECTOR. 5. INSTALL THE SERVICE ACTUATOR HARNESS 5-PIN CONNECTOR INTO THE AXLE ACTUATOR. 6. CONNECT JUMPER HARNESS 2X2 CONNECTOR INTO THE EXISTING VEHICLE 4WD MATING CONNECTOR. 7. STRAP THE JUMPER HARNESS AND THE SERVICE HARNESS TO THE TAB ON THE AXLE TUBE.

PARTS INFORMATION:

P/N DESCRIPTION QTY --- ----------- ---

26060073 ACTUATOR ASM, FRT DRIVE AXLE 1 22510339 FASTENER 1 15313272 HARNESS, JUMPER (Z SPLICE)(88-93 K1-3) 1

AXLE CODE 12376316 KIT, ACTUATOR WIRING HARNESS (88-96I K1,2) ZLS, ZLT, ZLW ZLX, ZLY 12376317 KIT, ACTUATOR WIRING HARNESS (96I-97 K1,2) ZWA, ZWB, ZWD ZWF, ZWG 12376318 KIT, ACTUATOR WIRING HARNESS (94-96I K3) ZLX, ZLY, ZLZ 12376319 KIT, ACTUATOR WIRING HARNESS (96I-97 K3) ZWF, ZWG, ZWH

PARTS, EXCEPT P/N 15313272, ARE CURRENTLY AVAILABLE FROM GMSPO. P/N 15313272 IS EXPECTED TO BE AVAILABLE 9-21-98.

WARRANTY INFORMATION:

SOME OWNERS WITH ACTUATORS THAT ARE OPERATING AS DESIGNED (5-30 SECONDS ENGAGEMENT TIME) MAY CHOOSE TO UPGRADE TO THE FAST ACTUATOR AT THEIR OWN EXPENSE. THE FAST ACTUATOR IS A NEW PRODUCT ENHANCEMENT AND SHOULD NOT BE USED TO REPLACE ACTUATORS THAT ARE OPERATING AS DESIGNED.

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION DESCRIPTION LABOR TIME --------- ----------- ----------

F0025 ACTUATOR, FRONT DIFFERENTIAL USE PUBLISHED LABOR LOCKING, REPLACE OPERATION TIME

N6112 WIRING AND/OR CONNECTOR-REPAIR USE PUBLISHED LABOR OPERATION TIME

IMPORTANT: LABOR OPERATION IS CODED TO BASE VEHICLE COVERAGE IN THE WARRANTY SYSTEM.

FIGURES: 00 ATTACHMENTS: 07

ATTACHMENT 1 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (94 TO CURRENT) ATTACHMENT 2 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (88-93 MODELS) ATTACHMENT 3 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (93 4L60E MODELS) ATTACHMENT 4 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (93 4L80E MODELS) ATTACHMENT 5 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (94 W/K3) ATTACHMENT 6 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (94 W/O K3) ATTACHMENT 7 - FOUR WHEEL DRIVE INDICATOR SCHEMATIC (95 TO CURRENT MODELS)

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.

COPYRIGHT 1998 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.



GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION


© Copyright General Motors Corporation. All Rights Reserved.


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Document ID# 533269
1993 Chevrolet/Geo Chevy Suburban - 4WD

[J-Ri]

Originally Posted by gearclash

CORRECTION:

REPLACE THE FRONT AXLE ACTUATOR AND INCLUDE THE APPLICABLE WIRING HARNESS KIT. REFER TO THE PARTS INFORMATION IN ORDER TO DETERMINE WHICH WIRING HARNESS KIT IS NEEDED.

Did they give you the right one?

If they did, according to the above post, you now have a motor. The exrta wire may be a power or a ground. It could also be a part that will replace a 3 wire OR a 4 wire stock part. Call the dealer, they should know

[gearclash]

Originally Posted by J-Ri

Did they give you the right one?

If they did, according to the above post, you now have a motor. The exrta wire may be a power or a ground. It could also be a part that will replace a 3 wire OR a 4 wire stock part. Call the dealer, they should know

J-Ri is correct, the new style actuator is a motor. The original was a termal type. The extra brown wire conects into the transfer case wiring, as my previous post with the sevice bulletin says. The atachment point varies by applicaion, usually near a switch on the transfer case. The dealer will have a copy of the service bulletin, though they sometimes can be hard to deal with. If you go to the dealer you bought the part at, they should help you out. Have them refer to the bulletin number I listed in my previous post. Don't forget to put in the metal "slug" that comes with the harness kit if yours came with one. Make sure you waterproof the splice you make into the wiring with silicon or some other method. Good luck!

[gearclash]

Originally Posted by gearclash

J-Ri is correct, the new style actuator is a motor. The original was a termal type. The extra brown wire conects into the transfer case wiring, as my previous post with the sevice bulletin says. The atachment point varies by applicaion, usually near a switch on the transfer case. The dealer will have a copy of the service bulletin, though they sometimes can be hard to deal with. If you go to the dealer you bought the part at, they should help you out. Have them refer to the bulletin number I listed in my previous post. Don't forget to put in the metal "slug" that comes with the harness kit if yours came with one. Make sure you waterproof the splice you make into the wiring with silicon or some other method. Good luck!

I also found this post in another thread here in AutomotiveForums.

Jeremy-WI
AF Enthusiast
Joined: Jan 2004
Posts: 552

12-07-2004, 05:01 AM Re: 4 Wheel Drive Help (Post #4)
On a vehicle updated with the new actuator, check the TCASE and 4x4 fuses to make sure they are good. With the ignition on and a 4 wheel drive mode selected, at the front actuator harness you should have 12v at the brown and light blue wire. With igntion on and 2WD selected you should have power only at the brown wire

[Dennis Iverson]

I have a 1995 k1500 the actuator stopped working t. replaced with new one did not work
checked power at the plug 12volts when put in 4high ! Ordered new actuator installed that one did the
same thing. checked power at the plug with test light nice bright then plugged in new actuator unplugged right a way and checked power very dim light waited for 30 -40 seconds like someone flipped a switch and the light was bright 12volt . I also did the same test on the three wires on the top of the transfercase right by the shifter. unplugged and tested for power found the brown was the only one with power. checked nice bright light. plugged it back then unplugged again checked dim light again just held it there again and about 30-40 seconds click back to full power again. looking for switch must be internal is there a relay in that line or something ?? I tried the Actuator direct to the battery and it worked fine . I t was the thermal actuator same as the old one . the electric one is a upgrade But like I sayed I hooked my old actuator direct to the battery posts and it worked fine ? My problem is when put it in4 wheel there is a problem like a rely in the line or something and not giving the actuator full 12 volts ?at the actuator there is only two wires at the plug on the tranfercase three.