Last post on Dec 20, 2011 at 8:53 AM
You are in the Isuzu Trooper
What is this discussion about?
Isuzu Ascender, Isuzu Trooper, SUV
Your Community Leader is paisan.
#3041 of 3299 Re: 2001 Trooper TOD problems [jgomez123]
Jun 27, 2006 (9:02 am)
Hi again, found this:
2001 Isuzu Truck Trooper LTD 4WD V6-3.5L
Vehicle Level Brakes and Traction Control Antilock Brakes / Traction Control Systems Testing and Inspection Antilock Brake System Trouble Code Diagnostic Procedures By Diagnostic Trouble Code (DTC) Number DTC 14 - B-2 EHCU Abnormality
DTC 14 - B-2 EHCU Abnormality
By Diagnostic Trouble Code (DTC) Number
2001 Isuzu Truck Trooper LTD 4WD V6-3.5L
Vehicle Level Brakes and Traction Control Antilock Brakes / Traction Control Systems Testing and Inspection Antilock Brake System Trouble Code Diagnostic Procedures By Diagnostic Trouble Code (DTC) Number DTC 24 - B7 Transfer Monitor
DTC 24 - B7 Transfer Monitor
By Diagnostic Trouble Code (DTC) Number
Okay, I found these, hope they help. also, just from experience, I know that your brake light switch is an integral part of the system and is monitored by the powertrain control module. You might check to see if it is adjusted correctly, if it is telling the tod module the brakes are on, it will effect the engagement speeds of the tod significantly. Just a tip that will at least eliminate one possible source of problems, particularly if it is intermittent.The TOD unit is under the passenger seat, might want to check the connector on that. Also, it monitors a speed sensor for the front driveshaft and another on the rear. Those connectors are on the transfer case near the the respective output shaft to the propeller shafts.
To me, it seems as though your TOD ECU is seeing some differences in speed from the front to rear, and applying torque to balance. If you want info on the speed sensors, Post again and I will dig deeper.
Remember to disconnect the battery cable if you are going to disconnect and reconnect any connectors. I think these are pretty easy things to check and then go from there. Good luck.
#3042 of 3299 Re: 2001 Trooper TOD problems [atfdmike]
Jun 27, 2006 (9:54 am)
I understood all of that, but what does EHCU stand for and where is it located?
#3043 of 3299 Re: 2001 Trooper TOD problems [jgomez123]
Jun 27, 2006 (12:39 pm)
EHCU = ElectroHydraulic Control Unit
I'm sure one of the owners will be able to tell you what it does and where to find it.
#3044 of 3299 Re: TOD FLUID [millejo1]
Jun 27, 2006 (6:21 pm)
I had the exact same thing happen, starter on friday, TOD flashing the next day. Did you get the check flashing to stop?
#3045 of 3299 Re: 2001 Trooper TOD problems [jgomez123]
Jun 28, 2006 (3:12 am)
The ehcu is your antilock brake controller. I don't think that this is where your problem lies as long as you are not getting fault codes for the brake system. It does monitor wheel rotation, and I don't know how or if that information is used by the vehicle other than for stopping. The diagnosis chart just has you taking it out of the loop so to speak for a voltage check on one pin. Again, not a bad idea to carefully disconnect and inspect the connector, cleaning with contact cleaner if necessary.
Electronic Hydraulic Control Unit (EHCU)
The EHCU consists of ABS control circuits, fault detector, and a fail-safe. It drives the hydraulic unit according to the signal from each sensor, canceling ABS to return to normal braking when a malfunction has occurred in the ABS.
The EHCU has a self-diagnosing function which can indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment front right side. It consists of a Motor, Plunger Pump, Solenoid Valves and Check Valve.
On the outside, the relay box containing a motor relay and a valve relay is installed.
Solenoid Valves: Reduces or holds the caliper fluid pressure for each front disc brake or both rear disc brakes according to the signal sent from the EHCU.
Reservoir: Temporarily holds the brake fluid that returns from the front and rear disc brake caliper so that pressure of front disc brake caliper can be reduced smoothly.
Plunger Pump: Feeds the brake fluid held in the reservoir to the master cylinder.
Motor: Drives the pump according to the signal from EHCU.
Check Valve: Controls the brake fluid flow.
Hope this helps.
#3046 of 3299 98 Isuzu Trooper, 3.5l, 89k miles, Maintenance issues
Jun 28, 2006 (4:48 am)
Iíve been good at changing the oil regularly but that's about it. Should I get the timing belt changed and the water pump at the same time? Are the troopers timing belts prone to breaking? What else should I get done? So far it runs great. Thanks in advance for your help!
#3047 of 3299 Re: 2001 Trooper TOD problems [atfdmike]
Jun 28, 2006 (2:12 pm)
Thank you very much. Before my starter died I had and continue to have this rubbing or grinding sound. It sounds like I have a low tire but I dont. Like the back tire is rubbing against something as it turns. Could it be the ABS. Also my flashing check TOD light goes off when I push the 4WD button on. Any ideas what the grinding/rubbing sound is? The tire pressures are good.
#3048 of 3299 Re: 98 Isuzu Trooper, 3.5l, 89k miles, Maintenance issues [eric138109]
Jun 29, 2006 (11:05 am)
Hi, here is what Isuzu says about your vehicles' timing belt. Generally, it is a good maintenance practice to change the water pump as having to do it if it fails means performing the same work to change the timing belt again. I don't know that they are prone to breaking, but since they extended the service life with this technical service bulletin, It would seem prudent to follow their advice.
1998 Isuzu Truck Trooper LTD V6-3.5L
Vehicle Level Engine, Cooling and Exhaust Engine Timing Belt Technical Service Bulletins Maintenance - Timing Belt/Valve Clearance
Maintenance - Timing Belt/Valve Clearance
MAINTENANCE SCHEDULE INFORMATION: TIMING BELT REPLACEMENT
INTERVAL AND DOHC V6 VALVE ADJUSTMENT SCHEDULE
TIMING BELT REPLACEMENT
1998 Trooper (UX) / Rodeo (UE) / Amigo
In the past, the timing belt replacement for the above affected vehicles has been recommended at every 75,000 mile intervals, regardless of driving condition. It is now recommended that the timing belt replacement interval of the above 1998 Isuzu models follow the same timing belt replacement interval as its 1999 model year successor. The new recommended timing belt replacement interval is 100,000 miles for normal vehicle use, and 75,000 miles for vehicles driven under Severe Driving Conditions.
NOTE :If the vehicle is usually operated under the conditions corresponding to any severe driving conditions given below, it is recommended that maintenance services be performed at the interval listed under Severe Driving Conditions.
^ Towing a trailer, using a camper or car top carrier.
^ Repeated short trips of less than 8 km (5 miles) with outside temperature remaining below freezing.
^ Extensive idling and/or low speed driving for long distances, such as police, taxi or door-to-door delivery use.
^ Operating on dusty, rough, muddy or salt spread roads.
V6 VALVE ADJUSTMENT
1998-2000 VehiCROSS (VX) / Trooper
(UX) / Rodeo (UE) / Amigo (UA) V6 models
with "direct-attack" valvetrain.
For the above affected vehicles, periodic 60,000 mile valve clearance inspections are not required. Adjust if valve noise is evident or a rough idle condition exists.
NOTE :When checking valve clearances, adjustment is required only when the clearance (lash) is out of specification. Be sure to retorque the camshaft bearing cap bolts before checking and adjusting the valve clearance.
#3049 of 3299 Re: 2001 Trooper TOD problems [pacheaco]
Jun 29, 2006 (11:18 am)
I think the first thing would be to rule out the brake pad/shoe condition of your brake system. The ABS system does a self test but it does not sound like rubbing or cause any braking activity on its' own.
It appears that you have rear drum brakes. The rubbing sound could be anything from the backing plate contacting the drum as it revolves to some brake component rubbing on the inside of the drum.
Also, there is a wheel speed sensor that is in very close proximity to the moving drum and if dirt or an object got stuck it could conceivably make noise and affect the ABS system. If the noise goes away when you apply the brakes, it may simply be a shoe or spring rubbing on the drum while the brake is not applied, and should be repaired.
Sometimes powdered iron will build up in tight spots and cause a noise as well. I would suggest you inspect or have the brakes inspected soon. good Luck
#3050 of 3299 Re: 98 Isuzu Trooper, 3.5l, 89k miles, Maintenance issues [atfdmike]
Jun 30, 2006 (6:51 am)
I'm looking for a place in Memphis to change my timing belt ('00 Trooper LS). I did check with the local Isuzu/Chevy dealer and was quoted around $850 to replace the timing belt and change the water pump. Has anyone had this done and what did you pay?