A friend of mine has the following brake problem on a dual axle van and we are looking for help.
When the breakaway pin is pulled the front wheels lock but the rear wheels have very little to no braking.
When the break pedal is pushed we get the same result.
Manual electric brake lever pulled full on-all wheels lock very well.
Electric operation can be heard at all wheels when expected. eg. when pedal is pushed on etc.
Doesn't seem to be intermittent and all pins on the seven pin plug have been split properly.
Any clues?
swamp said
08:02 PM Mar 25, 2018
Hi
depends on how the break away is setup ??
A general check is whats needed on your brakes
Tyres all the same type and pressure
All 4 tyres evenly weighted
van loaded so it travels flat not up or down FLAT .
Bearings serviced
All brakes same age and condition
same linning wear
Adjusted properly
van have a load sharing suspension ?
Check manually operated
amperage draw each magnet
voltage at each magnet
How much volt drop ,, from back of controller
trailer connector car side volt check
trailer connector van side volts
volts at wheels
PREFER TO USE separate CONNECTOR
Size cable 8mmsq or 8b/s
Sparkster said
08:18 AM Mar 26, 2018
Sorry, should have mentioned these checks were done with each side jacked up off the ground.
dorian said
08:35 AM Mar 26, 2018
How difficult would it be to swap the connections between a front and back wheel, either at the wheel or the controller? That should help to isolate the source of the problem.
Sparkster said
09:14 AM Mar 26, 2018
Thanks Dorian, I haven't looked at that but probably not all that difficult.
However when the lever on the break controller is pulled full on they all work OK (?).
dorian said
09:46 AM Mar 26, 2018
Sparkster wrote:
However when the lever on the break controller is pulled full on they all work OK (?).
The braking power would be controlled via Pulse Width Modulation (PWM). That is, the solenoid would be rapidly pulsed on and off with a duty cycle that varies according to braking effort. When the lever is full on, the duty cycle would be 100%.
ISTM that there may be an imbalance in the setting for the front and rear brakes. If so, then that should show up as a voltage difference. For example, the front axle may have a duty cycle of 100% while the rear may be set at 50% (under certain conditions).
Sparkster said
11:15 AM Mar 26, 2018
Thanks dorian, I'll see if I can round up my friend and do some voltage and current checks-much appreciated.
darjak said
09:35 PM Mar 27, 2018
It might be magnets had similar problem changed them solved my problem.
Also check electrical connection at wheel most are just crimped, as IMHO all should
be soldered and heat shrink used. I fill my heat shrink up with silicon before shrinking
makes the joint totally waterproof.
A friend of mine has the following brake problem on a dual axle van and we are looking for help.
Doesn't seem to be intermittent and all pins on the seven pin plug have been split properly.
Any clues?
depends on how the break away is setup ??
A general check is whats needed on your brakes
Tyres all the same type and pressure
All 4 tyres evenly weighted
van loaded so it travels flat not up or down FLAT .
Bearings serviced
All brakes same age and condition
same linning wear
Adjusted properly
van have a load sharing suspension ?
Check manually operated
amperage draw each magnet
voltage at each magnet
How much volt drop ,, from back of controller
trailer connector car side volt check
trailer connector van side volts
volts at wheels
PREFER TO USE separate CONNECTOR
Size cable 8mmsq or 8b/s
Thanks Dorian, I haven't looked at that but probably not all that difficult.
However when the lever on the break controller is pulled full on they all work OK (?).
The braking power would be controlled via Pulse Width Modulation (PWM). That is, the solenoid would be rapidly pulsed on and off with a duty cycle that varies according to braking effort. When the lever is full on, the duty cycle would be 100%.
ISTM that there may be an imbalance in the setting for the front and rear brakes. If so, then that should show up as a voltage difference. For example, the front axle may have a duty cycle of 100% while the rear may be set at 50% (under certain conditions).
Thanks dorian, I'll see if I can round up my friend and do some voltage and current checks-much appreciated.
Also check electrical connection at wheel most are just crimped, as IMHO all should
be soldered and heat shrink used. I fill my heat shrink up with silicon before shrinking
makes the joint totally waterproof.